Record 1 of 362

Title: Generation of correlated biphoton via four-wave mixing coexisting with multi-order fluorescence processes

Author(s): Liu, Y (Liu, Yang); Li, KK (Li, Kangkang); Zhang, SQ (Zhang, Siqiang); Fan, HR (Fan, Huanrong); Li, W (Li, Wei); Zhang, YP (Zhang, Yanpeng)

Source: SCIENTIFIC REPORTS  Volume: 9  Article Number: 20065  DOI: 10.1038/s41598-019-56567-9  Published: DEC 27 2019  

Abstract: We investigate the parametrically amplified four-wave mixing, spontaneous parametric four-wave-mixing, second- and fourth-order fluorescence signals coming from the four-level double-Lambda electromagnetically induced transparency system of a hot Rb-85 atomic vapor. The biphoton temporal correlation is obtained from spontaneous parametric four-wave-mixing and fourth-order fluorescence processes. Meanwhile, we first observed the biphoton Rabi oscillation with a background of linear Rayleigh scattering and uncorrelated second-order fluorescence. The outcomes of the investigation may contribute potentially to the applications in dense coding quantum communication systems.

Accession Number: WOS:000509327800011

PubMed ID: 31882802

Author Identifiers:

ISSN: 2045-2322

Record 2 of 362

Title: Direct observation and characterization of optical guiding of microparticles by tightly focused non-diffracting beams

Author(s): Liang, YS (Liang, Yansheng); Yan, SH (Yan, Shaohui); Yao, BL (Yao, Baoli); Lei, M (Lei, Ming)

Source: OPTICS EXPRESS  Volume: 27  Issue: 26  Pages: 37975-37985  DOI: 10.1364/OE.381969  Published: DEC 23 2019  

Abstract: Due to the propagation-invariant and self-healing properties, nondiffracting beams are highly attractive in optical trapping. However, little attention has been paid to investigating optical guiding of microparticles in nondiffracting beams generated by high-numerical-aperture (NA) optics with direct visualization. In this letter, we report a technique for direct observation and characterization of optical guiding of microparticles in a tight focusing system. With this technique, we observed a parabolic particle guiding trajectory with a longitudinal distance of more than 100 mu m and a maximal lateral deviation of 20 mu m when using Airy beams. We also realized the tilted-path transport of microparticles with controllable guiding direction using tilted zeroth-order quasi-Bessel beams. For an NA of the focusing lens equal to 0.95, we achieved the optical guiding of microparticles along a straight path with a tilt angle of up to 18.8 degrees with respect to the optical axis over a distance of 300 mu m. Importantly, quantitative measurement of particle's motion was readily accessed by measuring the particle's position and velocity during the transport process. The reported technique for direct visualization and characterization of the guided particles will find its potential applications in optical trapping and guiding with novel nondiffracting beams or accelerating beams. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Accession Number: WOS:000507254300074

PubMed ID: 31878569

Author Identifiers:

ISSN: 1094-4087

Record 3 of 362

Title: High Quality, Mass-Producible Semipolar GaN and InGaN Light-Emitting Diodes Grown on Sapphire

Author(s): Song, J (Song, Jie); Han, J (Han, Jung)

Source: PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS  Volume: 257  Issue: 4  Special Issue: SI  Article Number: 1900565  DOI: 10.1002/pssb.201900565  Early Access Date: DEC 2019   Published: APR 2020  

Abstract: The heteroepitaxy efforts of semipolar and nonpolar GaN grown on foreigner substrates are reviewed and summarized in the past 20 years. With the demonstration of three representative semipolar GaN grown on sapphire, the capability to produce semipolar GaN with any orientation on sapphire is exhibited. Also, a unique growth technology called facet-engineered orientation-controlling growth to eliminate the stacking faults (SFs) in semipolar GaN is developed and SF-free (202 over bar 1) GaN grown on sapphire is presented, demonstrating the capability of producing device-quality, large-area semipolar GaN. InGaN green light-emitting diodes (LEDs) grown on the SF-free semipolar (202 over bar 1) GaN/sapphire templates are performed with much higher external quantum efficiency in comparison with the typical semipolar/nonpolar LEDs heteroepitaxially grown on foreigner substrates reported before.

Accession Number: WOS:000502944200001

Author Identifiers:

ISSN: 0370-1972

eISSN: 1521-3951

Record 4 of 362

Title: Artificial compound eye-tipped optical fiber for wide field illumination

Author(s): Liu, F (Liu, Feng); Qing, Y (Qing, Yang); Bian, H (Bian, Hao); Zhang, F (Zhang, Fan); Hou, X (Hou, Xun); Kong, DP (Kong, Depeng); Chen, F (Chen, Feng)

Source: OPTICS LETTERS  Volume: 44  Issue: 24  Pages: 5961-5964  DOI: 10.1364/OL.44.005961  Published: DEC 15 2019  

Abstract: In this Letter, we present a novel, to the best of our knowledge, component with beam delivering and wide field beam homogenizing functions by grafting an artificial compound eye (ACE) micro-structure onto the polymer optical fiber (POF) end face. The 3D ACE mold is fabricated by ferntosecond laser-assisted micro machining, and the ACE micro-structure is transferred onto the end face through high accuracy nano-imprinting. The resultant POF end face integrates over 400 spherical micro-lenses, enabling a 40% enhancement in both the acceptance angle and the effective numerical aperture. Meanwhile, the integrated ommatidia array serves as an outstanding beam homogenizer, shaping the output beam into quasi flat-top distribution, which demonstrates promise in wide field homogeneous illumination, by reflection and transmission imaging experiments in both visible and near infrared bands. (C) 2019 Optical Society of America

Accession Number: WOS:000510847400019

PubMed ID: 32628203

Author Identifiers:

ISSN: 0146-9592

eISSN: 1539-4794

Record 5 of 362

Title: Microwave and RF Photonic Fractional Hilbert Transformer Based on a 50 GHz Kerr Micro-Comb

Author(s): Tan, MX (Tan, Mengxi); Xu, XY (Xu, Xingyuan); Corcoran, B (Corcoran, Bill); Wu, JY (Wu, Jiayang); Boes, A (Boes, Andreas); Nguyen, TG (Nguyen, Thach G.); Chu, ST (Chu, Sai T.); Little, BE (Little, Brent E.); Morandotti, R (Morandotti, Roberto); Mitchell, A (Mitchell, Arnan); Moss, DJ (Moss, David J.)

Source: JOURNAL OF LIGHTWAVE TECHNOLOGY  Volume: 37  Issue: 24  Pages: 6097-6104  DOI: 10.1109/JLT.2019.2946606  Published: DEC 15 2019  

Abstract: We report a photonicmicrowave and radio frequency (RF) fractional Hilbert transformer based on an integrated Kerr micro-comb source. The micro-comb source has a free spectral range (FSR) of 50 GHz, generating a large number of comb lines that serve as a high-performance multi-wavelength source for the transformer. By programming and shaping the comb lines according to calculated tap weights, we achieve both arbitrary fractional orders and a broad operation bandwidth. We experimentally characterize the RF amplitude and phase response for different fractional orders and perform system demonstrations of real-time fractional Hilbert transforms. We achieve a phase ripple of <0.15 rad within the 3-dB pass-band, with bandwidths ranging from 5 to 9 octaves depending on the order. The experimental results showgood agreement with theory, confirming the effectiveness of our approach as a new way to implement high-performance fractional Hilbert transformers with broad processing bandwidth, high reconfigurability, and greatly reduced size and complexity.

Accession Number: WOS:000508237300015

Author Identifiers:

ISSN: 0733-8724

eISSN: 1558-2213

Record 6 of 362

Title: Planar and ridge waveguides in Yb<SUP>3+</SUP>-doped silicate glasses fabricated by proton implantation and precise diamond blade dicing

Author(s): Zhang, J (Zhang, Jie); Guo, WT (Guo, Wen-Tao); Tang, CY (Tang, Chen-Yang); Yan, S (Yan, Sen); Li, WN (Li, Wei-Nan); Liu, CX (Liu, Chun-Xiao)

Source: OPTICS COMMUNICATIONS  Volume: 453  Article Number: 124344  DOI: 10.1016/j.optcom.2019.124344  Published: DEC 15 2019  

Abstract: We firstly report on the planar waveguide via the single-energy proton implantation in the Yb3+-doped silicate glass. The implanted energy and fluence are 400 keV and 8.0x10(16) ions/cm(2), respectively. The thermal treatment at 200 degrees C for lh was used to optimize waveguiding characteristics. The guided-mode spectra in the planar waveguide before and after annealing were characterized by the m-line method at 632.8 and 1539 nm. The distributions of refractive index for the as-implanted and annealed planar waveguides were reconstructed by the reflectivity calculation method. The optical characterizations were conducted at 632.8 nm using the end-fire coupling method before and after the thermal treatment. Then, the ridge waveguide was formed by the precise diamond blade dicing on the annealed planar Yb3+-doped silicate glass waveguide. The microscope image and near-field intensity profile of the ridge waveguide were investigated by the metallographic microscope and the end-face coupling system, respectively.

Accession Number: WOS:000487257300015

ISSN: 0030-4018

eISSN: 1873-0310

Record 7 of 362

Title: Experimental demonstration of wave-front coded imaging with a very low response of the modulation transfer function at the Nyquist frequency

Author(s): Zhao, H (Zhao, Hui); Mi, J (Mi, Jiao); Yu, CC (Yu, Congcong); Ge, R (Ge, Rui); Fan, XW (Fan, Xuewu)

Source: APPLIED OPTICS  Volume: 58  Issue: 35  Pages: 9562-9569  DOI: 10.1364/AO.58.009562  Published: DEC 10 2019  

Abstract: Wave-front coding (WFC) is a well-known technique that can be used to extend the depth of field (DOF) of incoherent imaging systems. The phase masks make the optical transfer function drop significantly, and digital restoration must be used to obtain a clear image with a largely extended DOF. According to the existing literature, in order to obtain satisfactory restoration results, the optical modulation transfer function (MTF) at the Nyquist frequency is required to be bigger than 0.1, which has already become a popularly accepted design constraint. However, according to our experimental research reported in this paper, this requirement is overly strict. By assembling one already fabricated WFC lens and another camera having physically higher resolution, the MTF of the newly assembled WFC system used in the experimentation has quite a low response at its Nyquist frequency. The experimental results demonstrate that when the optical MTF value at the Nyquist frequency reaches the minimum value of about 0.05, visually satisfactory restoration results can still be obtained as long as the MTF is optimized to be highly insensitive to defocus and the corresponding SNR of the coded intermediate images goes beyond 20 dB at the same time. The experimental results indicate that the overly strict constraint could be alleviated while designing a WFC system. (C) 2019 Optical Society of America

Accession Number: WOS:000502086200010

PubMed ID: 31873560

ISSN: 1559-128X

eISSN: 2155-3165

Record 8 of 362

Title: Controlled Asymmetric Bidirectional Hybrid of Remote State Preparation and Quantum Teleportation

Author(s): Huo, GW (Huo, Guang-Wen); Zhang, TY (Zhang, Tong-Yi); Zha, XW (Zha, Xin-Wei); Zhang, MZ (Zhang, Mei-Zhi)

Source: INTERNATIONAL JOURNAL OF THEORETICAL PHYSICS  Volume: 59  Issue: 2  Pages: 331-337  DOI: 10.1007/s10773-019-04326-x  Early Access Date: DEC 2019   Published: FEB 2020  

Abstract: We propose a protocol of Asymmetric implementing controlled joint remote state preparation and meanwhile realizing controlled quantum teleportation. That is to say, Alice wants to teleport an arbitrary two-qubit state to Bob, and Bob wants to remotely prepare a known state for Alice via the control of supervisors Charlie. Compared with previous studies for the schemes of solely bidirectional quantum teleportation, the new protocol is a kind of hybrid approach of information communication which makes the quantum channel multipurpose.

Accession Number: WOS:000501160300002

ISSN: 0020-7748

eISSN: 1572-9575

Record 9 of 362

Title: Structured active fiber fabrication and characterization of a chemically high-purified Dy<SUP>3+</SUP>-doped chalcogenide glass

Author(s): Xiao, XS (Xiao, Xusheng); Xu, YT (Xu, Yantao); Cui, J (Cui, Jian); Liu, XG (Liu, Xiaogang); Cui, XX (Cui, Xiaoxia); Wang, XS (Wang, Xunsi); Dai, SX (Dai, Shixun); Guo, HT (Guo, Haitao)

Source: JOURNAL OF THE AMERICAN CERAMIC SOCIETY  Volume: 103  Issue: 4  Pages: 2432-2442  DOI: 10.1111/jace.16921  Early Access Date: DEC 2019   Published: APR 2020  

Abstract: By conventional melt-quenching techniques, a series of Dy3+-doped (0.1 to 1.0 wt%) Ga5Ge20Sb15S60 bulk glasses were fabricated and their potential for developing mid-infrared fiber laser beyond 4 mu m were evaluated, in which the optimal Dy3+ doping concentration was found to be 0.3 wt% and the largest laser quality factor value (sigma(e) x tau(mea) = 2.62 x 10(-23) cm(2) s) among all of the Dy3+-doped chalcogenide glass was obtained. On this basis, through using the chemical purification methods with chlorine gas combined with the dynamic distillation process, the high-purity GGSS glasses with low O-H and S-H absorptions were successfully fabricated, which was confirmed by the optimized mid-infrared linear transmittance and improved fluorescent lifetimes of Dy3+: H-6(13/2), H-6(11/2) levels. Furthermore, for the first time to the best of our knowledge, the Dy3+-doped, single-mode, and double-cladding chalcogenide fibers with the core/cladding ratios of 125:60:11 and 125:66:11.5 were achieved by a multistage rod-in-tube fiber drawing process and extrusion methods, respectively. The GeS2-based fiber exhibits excellent transmission performance at 1.0-5.0 mu m: 3.0 dB/m at 2.9 mu m (O-H), 2.4 dB/m at 4.1 mu m (S-H). Combining the advantages of high-purity, high doping concentration and single-mode double-cladding structure, the optimized active fiber should be an ideal efficient and low-threshold medium toward mid-infrared fiber laser beyond 4 mu m.

Accession Number: WOS:000500577200001

ISSN: 0002-7820

eISSN: 1551-2916

Record 10 of 362

Title: Master oscillator pulse nonlinear amplifier system based on all polarization-maintaining fiber

Author(s): Zhang, T (Zhang Tong); Zhang, WG (Zhang Wei-Guang); Cai, YJ (Cai Ya-Jun); Hu, XH (Hu Xiao-Hong); Feng, Y (Feng Ye); Wang, YS (Wang Yi-Shan); Yu, J (Yu Jia)

Source: ACTA PHYSICA SINICA  Volume: 68  Issue: 23  Article Number: 234204  DOI: 10.7498/aps.68.20190925  Published: DEC 5 2019  

Abstract: The erbium-doped fiber oscillators, especially mode-locked fiber oscillators for generating femtosecond pulses, cannot meet the requirements for most of modern industrial applications because they are resticted by the low power and the limited wavelength range. In order to solve this problem, lots of efforts have been made both theoretically and experimentally, to improve the chirped pulse amplification (CPA) technology. The emergence of CPA technology greatly enhances the energy of laser pulses. The broadening and compressing of the laser pulses are both always dependent on the improving of spatial optical components, such as grating pairs. However, the use of this kind of method can increase the complexity of the amplification system to a certain extent. This may be an essential reason why more and more researchers pay attention to all fiber amplification system. In this paper, the master oscillator pulse nonlinear amplifier system based on all polarization- maintaining fiber is proposed, which is mainly composed of an oscillator based on the semiconductor saturable absorption mirror and linear cavity, a two-stage amplification and a pulse compressor constructed by a single-mode conductive fiber with anomalous dispersion. Using this system, we obtain ultrashort laser pulses in the 1.5 nm band whose pulse width equals 44 fs and single pulse energy reaches about 1 nJ. The system is not only compact and miniaturized but also stable and reliable due to the all polarization-maintaining fiber. Subsequently, an MgO doped periodically poled lithium niobite crystal with a thickness of 1 mm is used to implement frequency doubling. The pulses from the system are accurately focused on a position where the crystal polarization period is 19.8 mu m with help of some wave plates and lenses. Adjusting the optical path reasonably and optimizing colliminated focusing parameters, the double-frequency pulse output with certral wavelength of 779 nm and average power of 60 W is obtained, in which the conversion efficiency reaches 30%. The result shows that the master oscillator pulse nonlinear amplifier system based on all polarization maintaining fiber can produce satisfactory ultrashort pulses. It is a new idea for generating the ultrashort femtosecond pulses in the near-infrared band.

Accession Number: WOS:000501344000014

Author Identifiers:

ISSN: 1000-3290

Record 11 of 362

Title: 1D Solitons in Saturable Nonlinear Media with Space Fractional Derivatives

Author(s): Shi, JC (Shi, Jincheng); Zeng, JH (Zeng, Jianhua)

Source: ANNALEN DER PHYSIK  Volume: 532  Issue: 1  Article Number: 1900385  DOI: 10.1002/andp.201900385  Early Access Date: DEC 2019   Published: JAN 2020  

Abstract: Two decades ago, standard quantum mechanics entered into a new territory called space-fractional quantum mechanics, in which wave dynamics and effects are described by the fractional Schrodinger equation. Such territory is now a key and hot topic in diverse branches of physics, particularly in optics driven by the recent theoretical proposal for emulating the fractional Schrodinger equation. However, the light-wave propagation in saturable nonlinear media with space fractional derivatives is yet to be clearly disclosed. Here, such nonlinear optics phenomenon is theoretically investigated based on the nonlinear fractional Schrodinger equation with nonlinear lattices-periodic distributions of either focusing cubic (Kerr) or quintic saturable nonlinearities-and the existence and evolution of localized wave structures allowed by the model are addressed. The model upholds two kinds of one-dimensional soliton families, including fundamental solitons (single peak) and higher-order solitonic structures consisting of two-hump solitons (in-phase) and dipole ones (anti-phase). Notably, the dipole solitons can be robust stable physical objects localized merely within a single well of the nonlinear lattices-previously thought impossible. Linear-stability analysis and direct simulations are executed for both soliton families, and their stability regions are acquired. The predicted solutions can be readily observed in optical experiments and beyond.

Accession Number: WOS:000500415500001

Author Identifiers:

ISSN: 0003-3804

eISSN: 1521-3889

Record 12 of 362

Title: Photochromic effect of transparent lead-free ferroelectric KSr₂Nb₅O₁₅ ceramics

Author(s): Cao, SY (Cao, Shuyao); Gao, F (Gao, Feng); Xu, J (Xu, Jie); Zhu, JH (Zhu, Jihong); Chen, Q (Chen, Qian); Guo, YT (Guo, Yiting); Li, LL (Li, Leilei); Liu, JT (Liu, Junting); Gao, T (Gao, Tong); Pawlikowska, E (Pawlikowska, Emilia); Szafran, M (Szafran, Mikolaj); Cheng, GH (Cheng, Guanghua)

Source: JOURNAL OF THE EUROPEAN CERAMIC SOCIETY  Volume: 39  Issue: 16  Pages: 5260-5266  DOI: 10.1016/j.jeurceramsoc.2019.08.009  Published: DEC 2019  

Abstract: Transparent KSr2Nb5O15 (KSN) lead-free ferroelectric ceramics have been synthesized via modified pressureless sintering method. A significant photochromic effect was observed for the transparent KSN ceramics prepared without rare-earth dopant modification. The piezoelectric properties depend on the grain orientations were investigated. The optical transmittance of the KSN ceramics is greater than 40% in the wavelength range of 530-800 nm. After NUV irradiation, the absorbance was enhanced by more than 40% in a broad visible range (more than 79%). The absorbance returned to the initial value after a thermal bleaching process. The results of the cycling tests and response experiments showed the stability and saturation of the photochromic effect. In addition, the possible photochromic mechanism of the KSN ceramics is discussed and the photochromic centers are identified. This transparent KSN ceramics exhibits an obvious photochromic effect and is a potential candidate materials for optical data storage and information recording applications.

Accession Number: WOS:000488140300018

Author Identifiers:

ISSN: 0955-2219

eISSN: 1873-619X

Record 13 of 362

Title: Ultrahigh-Q toroidal dipole resonance in all-dielectric metamaterials for terahertz sensing

Author(s): Chen, X (Chen, Xu); Fan, WH (Fan, Wenhui)

Source: OPTICS LETTERS  Volume: 44  Issue: 23  Pages: 5876-5879  DOI: 10.1364/OL.44.005876  Published: DEC 1 2019  

Abstract: By arranging two pairs of high-index dielectric disks into a unit cell, a novel, to the best of our knowledge, terahertz metamaterials sensor integrated with a microfluidic channel is proposed. With the introduction of a new way of symmetry breaking in the unit cell, the strong toroidal dipole response with ultrahigh- Q is excited and investigated, which is related to the existence of the trapped mode. The simulation results show that the calculated quality factor and the corresponding figure of merit (FoM) of this sensor can reach 3189 and 515, respectively. These advantages allow for the proposed structure to have potential applications in high-performance gases, liquids, and biological materials sensing. (C) 2019 Optical Society of America

Accession Number: WOS:000499141000059

PubMed ID: 31774802

Author Identifiers:

ISSN: 0146-9592

eISSN: 1539-4794

Record 14 of 362

Title: Low-Threshold 4/5 Octave-Spanning Mid-Infrared Frequency Comb in a LiNbO₃ Microresonator

Author(s): Fan, WC (Fan, Weichen); Lu, ZZ (Lu, Zhizhou); Li, W (Li, Wei); Wang, XY (Wang, Xinyu); Zhou, MY (Zhou, Mengyao); Wang, WQ (Wang, Weiqiang); Sun, QB (Sun, Qibing); Wang, GX (Wang, Guoxi); Cheng, D (Cheng, Dong); Wang, LR (Wang, Leiran); Zhang, WF (Zhang, Wenfu); Zhao, W (Zhao, Wei)

Source: IEEE PHOTONICS JOURNAL  Volume: 11  Issue: 6  Article Number: 6603407  DOI: 10.1109/JPHOT.2019.2949313  Published: DEC 2019  

Abstract: Mid-infrared (MIR) optical frequency combs (OFCs) are ideal light sources for precision metrology and can find extensive applications, especially in molecular spectroscopy and gas detection. Here the generation of mode-locked MIR frequency comb in a LiNbO3 microring through optimized slot-waveguide design is proposed. Such microcomb can span over four-fifths of an octave (ranging from similar to 2810 nm to similar to 4630 nm) with pump power as low as 50 mW, which can be applied to the 2f-3f self-referencing for fully stabilization and helpful to monolithic integration of the whole system. Further investigations on complex dynamical processes for the microcomb generation suggest that the intracavity soliton drifting caused by the third-order dispersion could be compensated by the self-steepening effect as introducing an additional drift through proper dispersion tailoring. This work could facilitate the low-threshold broadband MIR frequency comb generation technique, as well as provide a way to realize more delicate control of soliton microcombs in both temporal and spectral domain.

Accession Number: WOS:000502033100001

Author Identifiers:

ISSN: 1943-0655

eISSN: 1943-0647

Record 15 of 362

Title: Optimization of temporal gate by two-color chirped lasers for the generation of isolated attosecond pulse in soft X rays

Author(s): He, LW (He, Liwei); Yuan, GL (Yuan, Guanglu); Wang, K (Wang, Kan); Hua, WJ (Hua, Weijie); Yu, C (Yu, Chao); Jin, C (Jin, Cheng)

Source: PHOTONICS RESEARCH  Volume: 7  Issue: 12  Pages: 1407-1415  DOI: 10.1364/PRJ.7.001407  Published: DEC 1 2019  

Abstract: We propose a simple and efficient method to optimize two-color chirped laser pulses by forming a "temporal gate" for the generation of isolated attosecond pulses (IAPs) in soft X rays. We show that the generation process for higher and cutoff harmonics can be effectively limited within the temporal gate, and the harmonic emission interval can be further reduced with the help of phase-matching by only selecting the contribution from short-trajectory electrons. This two-color gating mechanism is verified by increasing the pulse duration, raising the gas pressure, and extending the target cutoff. Compared to the five-color waveform in Phys. Rev. Lett. 102, 063003 (2009), our waveform can be used to generate the IAP in the long-duration laser pulse while the cutoff energy is higher without the reduction of harmonic yields. Our work provides an alternative temporal gating scheme for the generation of IAPs by simultaneously improving the harmonic conversion efficiency, thus making the attosecond soft X rays an intense and highly time-resolved tabletop light source for future applications. (C) 2019 Chinese Laser Press

Accession Number: WOS:000500910500008

Author Identifiers:

ISSN: 2327-9125

Record 16 of 362

Title: Tumor tissue classification based on micro-hyperspectral technology and deep learning

Author(s): Hu, BL (Hu, Bingliang); Du, J (Du, Jian); Zhang, ZF (Zhang, Zhoufeng); Wang, Q (Wang, Quan)

Source: BIOMEDICAL OPTICS EXPRESS  Volume: 10  Issue: 12  Pages: 6370-6389  DOI: 10.1364/BOE.10.006370  Published: DEC 1 2019  

Abstract: In order to explore the application of hyperspectral technology in the pathological diagnosis of tumor tissue, we used microscopic hyperspectral imaging technology to establish a hyperspectral database of 30 patients with gastric cancer. Based on the difference in spectral-spatial features between gastric cancer tissue and normal tissue in the wavelength of 410-910 nm, we propose a deep-learning model-based analysis method for gastric cancer tissue. The microscopic hyperspectral feature and individual difference of gastric tissue, spatial-spectral joint feature and medical contact are studied. The experimental results show that the classification accuracy of proposed model for cancerous and normal gastric tissue is 97.57%, the sensitivity and specificity of gastric cancer tissue are 97.19% and 97.96% respectively. Compared with the shallow learning method, CNN can fully extract the deep spectral-spatial features of tumor tissue. The combination of deep learning model and micro-spectral analysis provides new ideas for the research of medical pathology. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Accession Number: WOS:000504447400023

PubMed ID: 31853405

ISSN: 2156-7085

Record 17 of 362

Title: Biomimetic Anti-Adhesive Surface Microstructures on Electrosurgical Blade Fabricated by Long-Pulse Laser Inspired by Pangolin Scales

Author(s): Li, C (Li, Chen); Yang, Y (Yang, Yong); Yang, LJ (Yang, Lijun); Shi, Z (Shi, Zhen)

Source: MICROMACHINES  Volume: 10  Issue: 12  Article Number: 816  DOI: 10.3390/mi10120816  Published: DEC 2019  

Abstract: The electrosurgical blade is the most common invasive surgical instrument in a cutting and hemostasis process; however, the blade easily leads to the adhesion of overheated soft tissues on the blades and induces a potential danger for the patients. To minimize the adhesive tissues, we proposed the one-step surface texturing method to fabricate anti-adhesive biomimetic scales on stainless steel 316L rapidly based on the self-organized surface microstructures induced by the long-pulse fiber laser, which was inspired by the excellent performances of anti-adhesion and anti-friction in the pangolin scales. The optimal formation parameters, chemical components, and crystal structures of the laser-induced self-organized surface microstructures were investigated in the experiments. Moreover, the underlying formation mechanism was revealed. The electrosurgical blades with biomimetic scales have hydrophobicity and a smaller frictional coefficient, which effectively reduced the adhesion of soft tissue.

Accession Number: WOS:000507337900004

PubMed ID: 31779111

Author Identifiers:

eISSN: 2072-666X

Record 18 of 362

Title: Experimental Studies on the Noise Properties of the Harmonics From a Passively Mode-Locked Er-Doped Fiber Laser

Author(s): Song, JZ (Song, Jiazheng); Hu, XH (Hu, Xiaohong); Wang, HS (Wang, Hushan); Duan, T (Duan, Tao); Wang, YS (Wang, Yishan); Liu, YS (Liu, Yuanshan); Zhang, JG (Zhang, Jianguo)

Source: IEEE PHOTONICS JOURNAL  Volume: 11  Issue: 6  Article Number: 1504911  DOI: 10.1109/JPHOT.2019.2937324  Published: DEC 2019  

Abstract: We experimentally investigate the noise properties of a homemade 586 MHz mode-locked laser (MLL). The variation of the timing jitter versus the harmonic order is measured, which is consistent with the theoretical analyses. The dominant contributions to the timing jitter are detailedly studied by analyzing the phase noises at different harmonic frequencies. For low-order harmonics, the intensity noise and relative-intensity-noise-coupled (RIN-coupled) jitter mainly contribute to the timing jitter, while for high-order harmonics, the amplified spontaneous emission (ASE) noise makes the dominant contribution. Then we find that a higher output ratio has an obvious improvement on reducing the timing jitter and suppressing the phase noise because of the shorter pulse duration and lower net cavity dispersion caused by the higher output ratio. Finally a comparison of the noise performance between the MLL and a commercial signal generator is made, which shows that the optically generated radio-frequency signal (OGRFS) has a lower phase noise at high offset frequencies, however the higher phase noise at low offset frequencies leads to a higher timing jitter than the commercial SG.

Accession Number: WOS:000494460400001

Author Identifiers:

ISSN: 1943-0655

eISSN: 1943-0647

Record 19 of 362

Title: An X-ray frequency modulation method and its application in X-ray communication

Author(s): Su, T (Su, Tong); Tang, LY (Tang, Liangyu); Li, Y (Li, Yao); Sheng, LZ (Sheng, Lizhi); Zhao, BS (Zhao, Baosheng)

Source: OPTIK  Volume: 199  Article Number: 163263  DOI: 10.1016/j.ijleo.2019.163263  Published: DEC 2019  

Abstract: X-ray communication (XCOM) is a novel space communication method with great potential. X-rays have much shorter wavelengths than both infrared and radio. In principle, XCOM can send more data for the same amount of transmission power, which could permit more efficient gigabits-per-second data rates for deep space missions. Besides, X-rays can pierce the hot plasma sheath that builds up as spacecraft hurdle through Earth's atmosphere at hypersonic speeds. However, some current technical limitations have made X-ray communication unable to fully release its theoretical advantages in space communications. Among them, the modulation of X-ray emission impacts significantly. For the requirements of high-flux, collimation, quasi-monochromatic X-ray emissions, as well as the exploration of X-ray frequency modulation, we propose an X-ray frequency modulation method for generating different energy X-rays by controlling the electron beam deflection based on an external electrostatic field. Different from all traditional on-off control methods, this scheme uses two specific X-ray energies indicate the digital signal 0 and 1, which makes X-ray frequency modulation possible. Based on this, we simulated the emission flux and energy distribution of two different targets. Simulation results indicate that this X-ray modulation method produce X-rays with up to 50 GHz modulation frequency, 10(14) cps X-ray emission flux, 99% monochrome, and 1.5 mrad divergence angle. Through this modulator, not only the communication distance and communication speed experience significant increases, but also the concept of X-ray communication, X-ray ranging and X-ray navigation can be realized as a three-in-one mission.

Accession Number: WOS:000506316400006

Author Identifiers:

ISSN: 0030-4026

eISSN: 1618-1336

Record 20 of 362

Title: Research on active polarization imaging experiments and key technologies in smoke and dust environment

Author(s): Xie, ML (Xie, Meilin); Liu, P (Liu, Peng); Ma, CW (Ma, Caiwen); Hao, W (Hao, Wei); Huang, W (Huang, Wei); Lian, XZ (Lian, Xuezheng); Li, ZG (Li, Zhiguo); Han, JF (Han, Junfeng)

Source: OPTIK  Volume: 198  Article Number: 163309  DOI: 10.1016/j.ijleo.2019.163309  Published: DEC 2019  

Abstract: For realizing the engineering application of key technologies in the long-range active polarization imaging system, an experimental platform is built to study the static active polarization imaging technology and related image fusion algorithm in the smoke and dust environment. In the experiments, 532 nm CW laser is used as illumination source after collimation and beam expansion, metal bullet model is used as detection target, smoke environment is created through smoke generator in organic glass hood, polarization direction can be rotated by the polarizer, the images are collected by Lumerera-LM135 camera. The analysis and handling on the images are conducted by the use of the MATLAB software. In the aspects of image information entropy, average gradient, spatial frequency and standard deviation, the polarization imaging effects in various environments are quantitatively compared and analyzed, and the imaging advantages of laser illumination and polarization imaging technology in smoke and dust environment and dim conditions are verified. In order to further improve the imaging quality of active polarization imaging technology, a polarization image fusion algorithm based on fuzzy adaptive is proposed after analyzing a large number of data acquired in the experiment.
The experimental results show that the active polarization imaging technology and the improved image fusion algorithm can improve the detection distance of optical system and image contrast, expand the digestible information of images for the long-range dim target imaging in low visibility environment, and provide important data reference and technology support for the application of this technology in shooting range.

Accession Number: WOS:000494480200054

ISSN: 0030-4026

eISSN: 1618-1336

Record 21 of 362

Title: Influences of group velocity dispersion on ultrafast pulse shaping in time lens

Author(s): Xie, P (Xie, Peng); Wen, Y (Wen, Yu); Wan, ZS (Wan, Zishen); Wang, YS (Wang, Yishan)

Source: PHYSICA SCRIPTA  Volume: 94  Issue: 12  Article Number: 125503  DOI: 10.1088/1402-4896/ab33d0  Published: DEC 2019  

Abstract: Time-lens technology is of significant interest in signal processing and optical communication. The impacts of group velocity dispersion (GVD) on ultrafast pulse shaping in a time-lens system based on four-wave mixing are explored in this paper. The output signals of temporal magnification and time-to-frequency conversion under different GVDs are theoretically investigated in detail. The simulation results imply that the femtosecond pulse is sensitive to GVD in propagation. GVD has an important effect on nonlinear parametric processes, which results in output signals presenting different pulse shapes and different frequency profiles. Furthermore, a model of silicon nitride waveguide with flat dispersion is proposed by finite element method and signal processing with negligible pulse distortion is realized in near-infrared region.

Accession Number: WOS:000484753200003

Author Identifiers:

ISSN: 0031-8949

eISSN: 1402-4896

Record 22 of 362

Title: Application of Gaussian fitting to the fast search of pulsar periodic

Author(s): Xu, N (Xu, Neng); Sheng, LZ (Sheng, Lizhi); Chen, C (Chen, Chen); Li, Y (Li, Yao); Su, T (Su, Tong); Zhao, BS (Zhao, Baosheng); Zheng, W (Zheng, Wei); Liu, CL (Liu, Chunliang)

Source: OPTIK  Volume: 198  Article Number: 163253  DOI: 10.1016/j.ijleo.2019.163253  Published: DEC 2019  

Abstract: In this paper, we provided a Gaussian fitting method for fast periodic search to improve the accuracy of chi-square method. And this method can be used for the pulse periodic search of X-ray Pulsar. Firstly, we built the fast search model based on the epoch folding procedure by employing the basic principle of the chi-square evaluation. Secondly, we simulated the distribution of chi-square value by applying the pulsar profile to the fast search model, and it is fitting well with the Gaussian function. Finally, the designed experiments indicated that applying Gaussian fitting to chi-square method can significantly improve period search accuracy.

Accession Number: WOS:000494480200040

Author Identifiers:

ISSN: 0030-4026

eISSN: 1618-1336

Record 23 of 362

Title: Single-Photon Reflectivity and Depth Imaging by Continuous Measurement of Arrival Time of Photons

Author(s): Yan, QR (Yan, Qiurong); Li, D (Li, Dan); Wang, YF (Wang, Yifan); Yang, YB (Yang, Yibing); Tang, LN (Tang, Linao); Wang, YH (Wang, Yuhao)

Source: IEEE PHOTONICS JOURNAL  Volume: 11  Issue: 6  Article Number: 6901914  DOI: 10.1109/JPHOT.2019.2945989  Published: DEC 2019  

Abstract: We demonstrate a reflectivity and depth imaging Lidar system based on a novel photon arrival time measurement method. In this method, the arrival time of photons in a scanning position is continuously measured with a common starting point. The number of laser pulses is counted by a specially designed field programmable gate array (FPGA) control module as the coarse time of arrival photon. Time interval between arrival photon and the nearest coming laser pulse is measured by a time-correlated single-photon counting (TCSPC) module as the fine time of arrival photon. Using the system, not only the single-photon counting imaging can be realized, but also the first photon imaging, the first two photons imaging, etc. can be realized. A photon statistical model based on the doubly stochastic Poisson point processes, a time-gated filtering algorithm, and the reflectivity algorithm based on maximum likelihood estimation are derived. High-sensitivity reflectivity and depth imaging with a resolution of 512 x 512 pixels are achieved. The experimental results show that the horizontal spatial resolution is 2 mm, the vertical depth resolution is 5.375 cm, and the average number of photons per pixel is less than 1.3 photons.

Accession Number: WOS:000497769500001

Author Identifiers:

ISSN: 1943-0655

eISSN: 1943-0647

Record 24 of 362

Title: A Bilinear Ranking SVM for Knowledge Based Relation Prediction and Classification

Author(s): Yu, SK (Yu, Shengkang); Li, X (Li, Xi); Zhao, XY (Zhao, Xueyi); Zhang, ZF (Zhang, Zhongfei); Wu, F (Wu, Fei); Wang, JD (Wang, Jingdong); Zhuang, YT (Zhuang, Yueting); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON BIG DATA  Volume: 5  Issue: 4  Pages: 588-600  DOI: 10.1109/TBDATA.2018.2843766  Published: DEC 2019  

Abstract: As an important and challenging problem, knowledge representation and inference are typically carried out in a knowledge embedding framework over a multi-relational knowledge graph, and thus have a wide range of applications such as semantic retrieval and question answering. In this paper, we propose a bilinear learning framework which performs cross-entity knowledge relation analysis in the continuous vector space (derived from knowledge embedding). In the framework, we effectively model the intrinsic correlations among different types of knowledge relations within a max-margin multi-relational ranking scheme, which jointly optimizes the tasks of entity embedding and cross-entity relation prediction in terms of multi-relational structures of the knowledge graph. Specifically, we devise a bilinear scoring function that aims to evaluate the confidence degree of semantic relation prediction for entity pairs through a multi-relational learning-to-rank pipeline. In essence, the pipeline formulates the problem of relation prediction for entity pairs as that of learning relation-specific ranking functions by max-margin optimization. Experimental results demonstrate the effectiveness of the proposed framework on two common benchmark datasets.

Accession Number: WOS:000501301600015

Author Identifiers:

ISSN: 2332-7790

Record 25 of 362

Title: Unsupervised Learning of Human Action Categories in Still Images with Deep Representations

Author(s): Zheng, YP (Zheng, Yunpeng); Li, XL (Li, Xuelong); Lu, XQ (Lu, Xiaoqiang)

Source: ACM TRANSACTIONS ON MULTIMEDIA COMPUTING COMMUNICATIONS AND APPLICATIONS  Volume: 15  Issue: 4  Article Number: 112  DOI: 10.1145/3362161  Published: DEC 2019  

Abstract: In this article, we propose a novel method for unsupervised learning of human action categories in still images. In contrast to previous methods, the proposed method explores distinctive information of actions directly from unlabeled image databases, attempting to learn discriminative deep representations in an unsupervised manner to distinguish different actions. In the proposed method, action image collections can be used without manual annotations. Specifically, (i) to deal with the problem that unsupervised discriminative deep representations are difficult to learn, the proposed method builds a training dataset with surrogate labels from the unlabeled dataset, then learns discriminative representations by alternately updating convolutional neural network (CNN) parameters and the surrogate training dataset in an iterative manner; (ii) to explore the discriminatory information among different action categories, training batches for updating the CNN parameters are built with triplet groups and the triplet loss function is introduced to update the CNN parameters; and (iii) to learn more discriminative deep representations, a Random Forest classifier is adopted to update the surrogate training dataset, and more beneficial triplet groups then can be built with the updated surrogate training dataset. Extensive experiments on four benchmark datasets demonstrate the effectiveness of the proposed method.

Accession Number: WOS:000512285800012

Author Identifiers:

ISSN: 1551-6857

eISSN: 1551-6865

Record 26 of 362

Title: Effect of cation vacancies on the optical and dielectric properties of KSr₂Nb₅O₁₅: A first-principles study

Author(s): Chen, Q (Chen, Qian); Gao, F (Gao, Feng); Xu, J (Xu, Jie); Wu, CY (Wu, Changying); Cao, SY (Cao, Shuyao); Guo, YT (Guo, Yiting); Pawlikowska, E (Pawlikowska, Emilia); Szafran, M (Szafran, Mikolaj); Cheng, GH (Cheng, Guanghua)

Source: JOURNAL OF THE AMERICAN CERAMIC SOCIETY  Volume: 103  Issue: 3  Pages: 1912-1926  DOI: 10.1111/jace.16909  Early Access Date: NOV 2019   Published: MAR 2020  

Abstract: Using first-principles calculations, the effect of cation vacancies on the electronic structures and optical characters of KSr2Nb5O15 (KSN) lead-free ferroelectrics are investigated. The calculated dielectric properties are demonstrated by the experimental results. The cation vacancies involve K+ vacancies (KSN-K), Sr2+ vacancies (KSN-Sr), and coexisting K+ and Sr2+ vacancies (KSN-K&Sr). When these cation vacancies exist in KSN, the unit cell volumes decrease, leading to phase transition from tetragonal to orthorhombic, and the cation vacancies show strong effects on the band gap of KSN, declining by 1.46%-9.46%. The optical properties including the static dielectric constants, refraction, and extinction coefficient of KSN-K, KSN-Sr, and KSN-K&Sr increase more than those of KSN without vacancies, but the reflectivity and loss function decrease. All structures with cation vacancies are mainly refractive in the 0-4 eV photon energy range and are reflective at 5-8 eV. The refractivity increases and reflectivity decreases after vacancies occur. KSN-Sr has the largest static dielectric constant while KSN-K&Sr has the smallest values. The dielectric constant can be adjusted in the range of 25% by controlling the cation vacancies. The calculated dielectric properties are in good agreement with the experimental results. The results pave the way to regulate the optical and dielectric properties of lead-free ferroelectrics by controlling different cation vacancies.

Accession Number: WOS:000499114200001

Author Identifiers:

ISSN: 0002-7820

eISSN: 1551-2916

Record 27 of 362

Title: Toroidal metasurfaces integrated with microfluidic for terahertz refractive index sensing

Author(s): Chen, X (Chen, Xu); Fan, WH (Fan, Wenhui)

Source: JOURNAL OF PHYSICS D-APPLIED PHYSICS  Volume: 52  Issue: 48  Article Number: 485104  DOI: 10.1088/1361-6463/ab3ea0  Published: NOV 27 2019  

Abstract: A terahertz refractive index sensor consisting of toroidal dipole resonance metasurface integrated with microfluidic channel is proposed. The excitation of toroidal dipole resonance in this metasurface and the localized electromagnetic field enhancement in microfluidic channel are investigated comprehensively. Numerical results show that the calculated quality factor and the corresponding figure of merit can reach 1103 and 244, much higher than previously reported terahertz metamaterials sensors. Moreover, the refractive index sensing capabilities of non-polar and polar liquids are also investigated, which demonstrate the resonant frequency shift does not depend on the losses of analytes and show this device can be used for sensing various materials, including highly absorptive materials. This proposed structure can be extended to work in other frequency regions and has potential applications in high performance gases, liquids and biological materials sensing.

Accession Number: WOS:000485742400003

Author Identifiers:

ISSN: 0022-3727

eISSN: 1361-6463

Record 28 of 362

Title: Wideband and compact TM-pass polarizer based on hybrid plasmonic grating in LNOI

Author(s): Yu, WQ (Yu, Wenqi); Dai, SX (Dai, Shuangxing); Zhao, QF (Zhao, Qinfeng); Li, JY (Li, Jinye); Liu, JG (Liu, Jianguo)

Source: OPTICS EXPRESS  Volume: 27  Issue: 24  Pages: 34857-34863  DOI: 10.1364/OE.27.034857  Published: NOV 25 2019  

Abstract: Based on the transverse electric (TE)/transverse magnetic (TM) polarization diversity in plasmonic Bragg gratings, a compact TM-pass/TE-stop polarizer is theoretically proposed on thin-film lithium niobate on insulator (LNOI) platforms. By introducing a large misalignment between metal gratings on both sides of the LNOI waveguide, we demonstrate a polarizer with a high extinction ratio of 20 dB, a low insertion loss of 2.5 dB, a wide waveband from 1.48 to 1.62 mu m, and a compact size of only 23 mu m on simulation. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Accession Number: WOS:000603035500028

PubMed ID: 31878665

Author Identifiers:

ISSN: 1094-4087

Record 29 of 362

Title: Modified eigenvector-based feature extraction for hyperspectral image classification using limited samples

Author(s): Wang, WN (Wang, Wenning); Mou, XQ (Mou, Xuanqin); Liu, XB (Liu, Xuebin)

Source: SIGNAL IMAGE AND VIDEO PROCESSING  Volume: 14  Issue: 4  Pages: 711-717  DOI: 10.1007/s11760-019-01604-3  Early Access Date: NOV 2019   Published: JUN 2020  

Abstract: Classical supervised feature extraction methods, such as linear discriminant analysis (LDA) and nonparametric weighted feature extraction (NWFE), and search for projection directions through which the ratio of a between-class scatter matrix to a within-class scatter matrix can be maximized. The two feature extraction methods can obtain good classification results when training samples are sufficient; however, the effect is nonideal when samples are insufficient. In this study, the eigenvector spectra of LDA and NWFE are modified using spectral distribution information, which is locally unstable under the condition of a few samples. Experiments demonstrate that the proposed method outperforms several conventional feature extraction methods.

Accession Number: WOS:000498145800001

ISSN: 1863-1703

eISSN: 1863-1711

Record 30 of 362

Title: Topographic Evolution of Von Karman Crater Revealed by the Lunar Rover Yutu-2

Author(s): Di, KC (Di, Kaichang); Zhu, MH (Zhu, Meng-Hua); Yue, ZY (Yue, Zongyu); Lin, YT (Lin, Yangting); Wan, WH (Wan, Wenhui); Liu, ZQ (Liu, Zhaoqin); Gou, S (Gou, Sheng); Liu, B (Liu, Bin); Peng, M (Peng, Man); Wang, YX (Wang, Yexin); Niu, SL (Niu, Shengli); Zhang, JH (Zhang, Jinhai); Li, J (Li, Jian); Xie, JF (Xie, Jianfeng); Xi, LH (Xi, Luhua); Yang, JF (Yang, Jianfeng); Xue, B (Xue, Bin)

Source: GEOPHYSICAL RESEARCH LETTERS  Volume: 46  Issue: 22  Pages: 12764-12770  DOI: 10.1029/2019GL085252  Early Access Date: NOV 2019   Published: NOV 28 2019  

Abstract: Chang'e-4 (CE-4) achieved the first farside landing in Von Karman crater. In the landing site, linear features have been identified previously from SLDEM and considered to be ejecta from the neighboring Finsen crater. The 5 cm grid spacing digital elevation model of the landing site, generated from the rover's panoramic images, provides more details of the rugged terrain. We further interpret the superimposition of NE-SW ejecta from Finsen crater on the underlying SE-NW dome-like surface relief from Alder crater. The landing site is similar to 70 m higher than the mare basalts within Von Karman crater. Numerical simulations predict similar to 30 and similar to 35 m ejecta deposited at the landing site from Finsen and Alder craters, respectively. The good agreement between the digital elevation model data and ejecta predicted thickness reveals the topographic evolution of Von Karman crater, indicating that the rover-measured material is excavated from Finsen crater with possible contributions from Alder crater.

Accession Number: WOS:000497908400001

Author Identifiers:

ISSN: 0094-8276

eISSN: 1944-8007

Record 31 of 362

Title: Imaging Enhancement of Light-Sheet Fluorescence Microscopy via Deep Learning

Author(s): Bai, C (Bai, Chen); Liu, C (Liu, Chao); Yu, XH (Yu, Xianghua); Peng, T (Peng, Tong); Min, JW (Min, Junwei); Yan, SH (Yan, Shaohui); Dan, D (Dan, Dan); Yao, BL (Yao, Baoli)

Source: IEEE PHOTONICS TECHNOLOGY LETTERS  Volume: 31  Issue: 22  Pages: 1803-1806  DOI: 10.1109/LPT.2019.2948030  Published: NOV 15 2019  

Abstract: The complementary beam subtraction (CBS) method can reduce the out-of-focus background and improve the axial resolution in light-sheet fluorescence microscopy (LSFM) via double scanning a Bessel and the complementary beams. With the assistance of a compressed blind deconvolution and denoising (CBDD) algorithm, the noise and blurring incurred during CBS imaging can be further removed. However, this approach requires double scanning and large computational cost. Here, we propose a deep learning-based method for LSFM, which can reconstruct high-quality images directly from the conventional Bessel beam (BB) light-sheet via a single scan. The image quality achievable with this CBS-Deep method is competitive with or better than the CBS-CBDD method, while the speed of image reconstruction is about 100 times faster. Accordingly, the proposed method can significantly improve the practicality of the CBS-CBDD system by reducing both scanning behavior and reconstruction time. The results show that this cost-effective and convenient method enables high-quality LSFM techniques to be developed and applied.

Accession Number: WOS:000516532800011

Author Identifiers:

ISSN: 1041-1135

eISSN: 1941-0174

Record 32 of 362

Title: Robust contrast-transfer-function phase retrieval via flexible deep learning networks: publisher's note (vol 44, pg 5141, 2019)

Author(s): Bai, C (Bai, Chen); Zhou, ML (Zhou, Meiling); Min, JW (Min, Junwei); Dang, SP (Dang, Shipei); Yu, XH (Yu, Xianghua); Zhang, P (Zhang, Peng); Peng, T (Peng, Tong); Yao, BL (Yao, Baoli)

Source: OPTICS LETTERS  Volume: 44  Issue: 22  Pages: 5561-5561  DOI: 10.1364/OL.44.005561  Published: NOV 15 2019  

Accession Number: WOS:000496981500044

PubMed ID: 31730108

Author Identifiers:

ISSN: 0146-9592

eISSN: 1539-4794

Record 33 of 362

Title: Aperture scalable liquid crystal optically duplicated array of phased array

Author(s): He, XX (He, Xiaoxian); Wang, XR (Wang, Xiangru); Wu, L (Wu, Liang); Liu, XP (Liu, Xiaopeng); Guo, HR (Guo, Hongru); Huang, XN (Huang, Xinning); Xie, XP (Xie, Xiaoping); Tan, QG (Tan, Qinggui); Cao, J (Cao, Jie)

Source: OPTICS COMMUNICATIONS  Volume: 451  Pages: 174-180  DOI: 10.1016/j.optcom.2019.06.037  Published: NOV 15 2019  

Abstract: To achieve non-mechanical laser beam steering in the scenario of long distance propagation such as free-space laser communication between satellites, large aperture size is an inevitable issue to be considered to narrow the divergence angle of the output beam. Liquid crystal optical phased array, to be one of the solutions of non-mechanical beam steering, has already shown its obvious potential to achieve a relative large aperture on the order of centimeter. To achieve even larger, its driving matrix becomes squared larger. In this paper, we proposed a novel architecture to realize an optical phased array with a scalable aperture. Meanwhile the driving matrix is almost not increased. It provides the feature of a cascade system with a device of spatial phased modulation and an array of duplicating units. Each unit of the duplicating array is consist of a polarization beam splitter and a half wave plate to have the same output optical field distribution as the input beam whose phase front is modulated by a small size spatial modulator. Not only the property of beam deflection is numerically simulated and experimentally verified, but also the property of divergence angle compression and grating lobes limitation are evaluated. Meanwhile, due to the high precision of the experimental alignment, the non-mechanical beam deflection property is still maintained no matter how many the duplicated unit number is. The relative standard derivation steering error is 0.025.

Accession Number: WOS:000480419300028

Author Identifiers:

ISSN: 0030-4018

eISSN: 1873-0310

Record 34 of 362

Title: Super-resolution imaging reveals changes in <i>Escherichia coli</i> SSB localization in response to DNA damage

Author(s): Zhao, TY (Zhao, Tianyu); Liu, Y (Liu, Yan); Wang, ZL (Wang, Zilin); He, RY (He, Rongyan); Zhang, JX (Zhang, Jia Xiang); Xu, F (Xu, Feng); Lei, M (Lei, Ming); Deci, MB (Deci, Michael B.); Nguyen, J (Nguyen, Juliane); Bianco, PR (Bianco, Piero R.)

Source: GENES TO CELLS  Volume: 24  Issue: 12  Pages: 814-826  DOI: 10.1111/gtc.12729  Early Access Date: NOV 2019   Published: DEC 2019  

Abstract: The E. coli single-stranded DNA-binding protein (SSB) is essential to viability. It plays key roles in DNA metabolism where it binds to nascent single strands of DNA and to target proteins known as the SSB interactome. There are >2,000 tetramers of SSB per cell with 100-150 associated with the genome at any one time, either at DNA replication forks or at sites of repair. The remaining 1,900 tetramers could constantly diffuse throughout the cytosol or be associated with the inner membrane as observed for other DNA metabolic enzymes. To visualize SSB localization and to ascertain potential spatiotemporal changes in response to DNA damage, SSB-GFP chimeras were visualized using a novel, super-resolution microscope optimized for the study of prokaryotic cells. In the absence of DNA damage, SSB localizes to a small number of foci and the excess protein is associated with the inner membrane where it binds to the major phospholipids. Within five minutes following DNA damage, the vast majority of SSB disengages from the membrane and is found almost exclusively in the cell interior. Here, it is observed in a large number of foci, in discreet structures or, in diffuse form spread over the genome, thereby enabling repair events.

Accession Number: WOS:000496241900001

PubMed ID: 31638317

Author Identifiers:

ISSN: 1356-9597

eISSN: 1365-2443

Record 35 of 362

Title: An efficient framework for unsupervised feature selection

Author(s): Zhang, H (Zhang, Han); Zhang, R (Zhang, Rui); Nie, FP (Nie, Feiping); Li, XL (Li, Xuelong)

Source: NEUROCOMPUTING  Volume: 366  Pages: 194-207  DOI: 10.1016/j.neucom.2019.07.020  Published: NOV 13 2019  

Abstract: In these years, the task of fast unsupervised feature selection attracts much attentions with the increasing number of data collected from the physical world. To speed up the running time of algorithms, the bipartite graph theory has been applied in many large-scale tasks, including fast clustering, fast feature extraction, etc. Inspired by this, we present a novel bipartite graph based fast feature selection approach named Efficient Unsupervised Feature Selection (EUFS). Compared to the existing methods focusing on the same topic, EUFS is advanced in two aspects: (1) we learn a high-quality discrete indicator matrix for these unlabelled data by virtue of bipartite graph based spectral clustering, instead of obtaining an implicit cluster structure matrix; (2) we learn a row-sparse matrix for evaluating features via a generalized uncorrelated regression model supervised by the achieved indicator matrix, which succeeds in exploring the discriminative and uncorrelated features. Correspondingly, the features selected by our model could achieve an excellent clustering or classification performance while maintaining a low computational complexity. Experimentally, the results of EUFS compared to five state-of-the-art algorithms and one baseline on ten benchmark datasets verifies its efficiency and superiority. (C) 2019 Published by Elsevier B.V.

Accession Number: WOS:000488202500019

Author Identifiers:

ISSN: 0925-2312

eISSN: 1872-8286

Record 36 of 362

Title: A Review of Functional Near-Infrared Spectroscopy Studies of Motor and Cognitive Function in Preterm Infants

Author(s): Wang, Q (Wang, Quan); Zhu, GP (Zhu, Guang-Pu); Yi, L (Yi, Li); Cui, XX (Cui, Xin-Xin); Wang, H (Wang, Hui); Wei, RY (Wei, Ru-Yi); Hu, BL (Hu, Bing-Liang)

Source: NEUROSCIENCE BULLETIN  Volume: 36  Issue: 3  Pages: 321-329  DOI: 10.1007/s12264-019-00441-1  Early Access Date: NOV 2019   Published: MAR 2020  

Abstract: Preterm infants are vulnerable to brain injuries, and have a greater chance of experiencing neurodevelopmental disorders throughout development. Early screening for motor and cognitive functions is critical to assessing the developmental trajectory in preterm infants, especially those who may have motor or cognitive deficits. The brain imaging technology functional near-infrared spectroscopy (fNIRS) is a portable and low-cost method of assessing cerebral hemodynamics, making it suitable for large-scale use even in remote and underdeveloped areas. In this article, we review peer-reviewed, scientific fNIRS studies of motor performance, speech perception, and facial recognition in preterm infants. fNIRS provides a link between hemodynamic activity and the development of brain functions in preterm infants. Research using fNIRS has shown different patterns of hemoglobin change during some behavioral tasks in early infancy. fNIRS helps to promote our understanding of the developmental mechanisms of brain function in preterm infants when performing motor or cognitive tasks in a less-restricted environment.

Accession Number: WOS:000495946000001

PubMed ID: 31713716

Author Identifiers:

ISSN: 1673-7067

eISSN: 1995-8218

Record 37 of 362

Title: Tripartite Einstein-Podolsky-Rosen steering with linear and nonlinear beamsplitters in four-wave mixing of Rubidium atoms

Author(s): Liu, Y (Liu, Yang); Cai, Y (Cai, Yin); Xiang, Y (Xiang, Yu); Li, F (Li, Feng); Zhang, YP (Zhang, Yanpeng); He, QY (He, Qiongyi)

Source: OPTICS EXPRESS  Volume: 27  Issue: 23  Pages: 33070-33079  DOI: 10.1364/OE.27.033070  Published: NOV 11 2019  

Abstract: Multipartite Einstein-Podolsky-Rosen (EPR) steering is an essential resource for secure one-sided device-independent quantum secret sharing. Here, we analyze the EPR steering properties exhibited in three-mode Gaussian states created by four-wave mixing (FWM) in Rubidium atoms combined with a linear beamsplitter and a nonlinear beamsplitter (second FWM), respectively. By quantifying Gaussian steerability based on a measure determined by the covariance matrix of the produced states, we compare the performance of two schemes to achieve one-way, collective, and genuine tripartite steering, as well as the monogamy constraints for distributing steering among three parties. We show that the scheme with nonlinear beamsplitter is feasible to create stronger bipartite steering and genuine tripartite steering and has more flexibility to manipulate the monogamy relation through the cooperation of the two cascaded FWM processes. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Accession Number: WOS:000495871300019

PubMed ID: 31878381

Author Identifiers:

ISSN: 1094-4087

Record 38 of 362

Title: Toward high contrast and high-resolution microscopic ghost imaging

Author(s): Sun, Z (Sun, Zhe); Tuitje, F (Tuitje, Frederik); Spielmann, C (Spielmann, Christian)

Source: OPTICS EXPRESS  Volume: 27  Issue: 23  Pages: 33653-33662  DOI: 10.1364/OE.27.033652  Published: NOV 11 2019  

Abstract: In this study, the influence of speckle size on contrast-to-noise ratio (CNR) and resolution is examined based on the object dimensions in the macroscopic and microscopic regimes. This research shows that for microscopic samples the conventional scaling laws are no longer effective and the CNR does not counter-propagate in the same manner as the resolution. To our knowledge, a deviation in CNR scaling on speckle size is observed for the first time in the field of microscopic ghost imaging. This result was verified using two different sample shapes. In addition, numerical analysis revealed that the noise of the photodiode is a limiting factor for the CNR. Based on these findings, the conditions for identifying the parameter set that maximizes the CNR and provides high resolution images was defined, which achieving high-quality microscopic ghost images. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Accession Number: WOS:000495871300066

PubMed ID: 31878428

Author Identifiers:

ISSN: 1094-4087

Record 39 of 362

Title: Disentangling the Luminescent Mechanism of Cs₄PbBr₆ Single Crystals from an Ultrafast Dynamics Perspective

Author(s): Liu, RT (Liu, Rui-Tong); Zhai, XP (Zhai, Xin-Ping); Zhu, ZY (Zhu, Zhi-Yuan); Sun, B (Sun, Bing); Liu, DW (Liu, Duan-Wu); Ma, B (Ma, Bo); Zhang, ZQ (Zhang, Ze-Qi); Sun, CL (Sun, Chun-Lin); Zhu, BL (Zhu, Bing-Li); Zhang, XD (Zhang, Xiao-Dong); Wang, Q (Wang, Qiang); Zhang, HL (Zhang, Hao-Li)

Source: JOURNAL OF PHYSICAL CHEMISTRY LETTERS  Volume: 10  Issue: 21  Pages: 6572-6577  DOI: 10.1021/acs.jpclett.9b02590  Published: NOV 7 2019  

Abstract: New all-inorganic perovskites like Cs4PbBr6 provide rich luminescent tools and particularly novel physical insights, including their zero-dimensional structure and controversial emitting mechanism. The ensuing debate over the origin of the luminescence of Cs4PbBr6 inspired us to tackle the issue through fabricating high-quality Cs4PbBr6 single crystals and employing ultrafast dynamics study. Upon photoexcitation, Cs4PbBr6 underwent dynamics steps distinct from that of CsPbBr3, including exciton migration to the defect level on a time scale of several hundred femtoseconds, exciton relaxation within the defect states on the picosecond time scale, and exciton recombination from the subnanosecond to nanosecond time scale. The observation disclosed that crystal defects of Cs4PbBr6 induced green emission while CsPbBr3 mainly relied on quantum confinement to emit at room temperature. The study provides an in-depth understanding of the photoinduced multistep dynamics steps of Cs4PbBr6 associated with display and photovoltaic applications, establishing Cs4PbBr6 as a new candidate for uses associated with the perovskite family of materials.

Accession Number: WOS:000495805100021

PubMed ID: 31594309

Author Identifiers:

ISSN: 1948-7185

Record 40 of 362

Title: Phase control and stabilization in attosecond beamline with fast Fourier transform

Author(s): Jiang, YJ (Jiang Yu-Jiao); Gao, YT (Gao Yi-Tan); Huang, P (Huang Pei); Zhao, K (Zhao Kun); Xu, SY (Xu Si-Yuan); Zhu, JF (Zhu Jiang-Feng); Fang, SB (Fang Shao-Bo); Teng, H (Teng Hao); Hou, X (Hou Xun); Wei, ZY (Wei Zhi-Yi)

Source: ACTA PHYSICA SINICA  Volume: 68  Issue: 21  Article Number: 214204  DOI: 10.7498/aps.68.20191164  Published: NOV 5 2019  

Abstract: With the unveiling of molecular and atomic dynamics, scientists crave finer and faster tools to communicate with the microworld. Attosecond pump-probe enjoys its reputation as the fastest camera, hinting ultrafast movements in the delay graph. To employ this camera, the stability and delay control should have very great accuracy comparable to the camera resolution. It is also of significant importance for stabilizing the carrier envelope phase (CEP) in few-cycle laser field. When dealing with a huge quantity of data, conventional Fourier transform algorism is challenging in high-speed control. Here we put forward the efficient calculation method, fast Fourier transform (FFT) algorism in Mach-Zehnder interferometer for arm length locking and f-2f for CEP locking. In the interferometer locking, 532 nm continuous wave laser is used in the Mach-Zehnder interferometer, and the phase of the FFT term corresponding to the delay between the two arms of the interferometer serves as a feedback signal on piezo transducer (PZT) in the delay line to reduce the change of the arm length. In the CEP control experiment, data to be analyzed are the f-2f spectrum interference fringes recorded by the spectrometer. The CEP values are obtained from the first order of FFT module output of the integrated spectrum interference fringes, and a labview program examines the relative phase drift and sends a feedback voltage signal to the PZT through the proportion integration differentiation module to compensate slow CEP drift after the chirped pulse amplification system by changing the insert length of a prism pair. The results show that the root mean square (RMS) of the arm length difference is 1.24 nm (4.1 attosecond for light to travel) per meter in the interferometer locking over 12 h, and the RMS of CEP is 227 mrad under 3 ms integration time in the CEP locking over 20 min. These results are able to meet the requirement of the accuracy for attosecond pulse generation and attosecond pump-probe experiments. We also use FFT to stabilize the CEP and relative time simultaneously in the waveform synthesis for 8 h (Huang P, Fang S, Gao Y, Zhao K, Hou X, Wei Z 2019 Appl. Phys. Lett. 115 031102), the phase-locking system results in a CEP stability of 280 mrad and a relative time stability of 110 as at a repetition rate of 1 kHz. These results imply that the FFT is versatile and reliable in ultrafast control.

Accession Number: WOS:000496172100009

Author Identifiers:

ISSN: 1000-3290

Record 41 of 362

Title: White-Light Image Reconstruction via Seeded Modulation Instability

Author(s): Zhang, YB (Zhang, Yongbin); Liu, HJ (Liu, Hongjun); Huang, N (Huang, Nan); Wang, ZL (Wang, Zhaolu)

Source: PHYSICAL REVIEW APPLIED  Volume: 12  Issue: 5  Article Number: 054005  DOI: 10.1103/PhysRevApplied.12.054005  Published: NOV 4 2019  

Abstract: Nonlinear imaging preserves more detailed information by exploiting the presence and interaction of many photons in nonlinear optics. Despite significant progress, nonlinear methods for white-light image recovery are still lacking. We report the white-light image reconstruction via seeded modulation instability, which is called dynamical stochastic resonance. The underlying signals are illuminated with white light emitted from a light-emitting diode and are reinforced by coupling with scattering noise in a noninstantaneous self-focusing medium. Our experimental results show that this nonlinear approach is effective in improving the contrast and visibility of completely blurred white-light images by guiding noise rather than by filtering noise. The signals of the entire temporal spectrum collectively seed a potential in the medium. In turn, the potential leads to the enhancement of signal modes by concentrating scattering noise. A theoretical growth rate is derived and the numerical simulations are presented to match the experimental observation. We also demonstrate that the underlying signals can be preferably reproduced by asynchronously probing the seeded potential with another white-light beam. Our work reveals an alternative scheme for white-light image detection.

Accession Number: WOS:000494035000002

Author Identifiers:

ISSN: 2331-7019

Record 42 of 362

Title: The Radiative Transfer Characteristics of the O₂ Infrared Atmospheric Band in Limb-Viewing Geometry

Author(s): He, WW (He, Weiwei); Wu, KJ (Wu, Kuijun); Feng, YT (Feng, Yutao); Fu, D (Fu, Di); Chen, ZW (Chen, Zhenwei); Li, FQ (Li, Faquan)

Source: REMOTE SENSING  Volume: 11  Issue: 22  Article Number: 2702  DOI: 10.3390/rs11222702  Published: NOV 2 2019  

Abstract: The O-2(a(1)Delta(g)) emission near 1.27 mu m provides an important means to remotely sense the thermal characteristics, dynamical features, and compositional structures of the upper atmosphere because of its photochemistry and spectroscopic properties. In this work, an emission-absorption transfer model for limb measurements was developed to calculate the radiation and scattering spectral brightness by means of a line-by-line approach. The nonlocal thermal equilibrium (non-LTE) model was taken into account for accurate calculation of the O-2(a(1)Delta(g)) emission by incorporating the latest rate constants and spectral parameters. The spherical adding and doubling methods were used in the multiple scattering model. Representative emission and absorption line shapes of the O-2(a(1)Delta(g), upsilon ' = 0) -> O-2(X-3 Sigma(g), upsilon '' = 0) band and their spectral behavior varying with altitude were examined. The effects of solar zenith angle, surface albedo, and aerosol loading on the line shapes were also studied. This paper emphasizes the advantage of using infrared atmospheric band for remote sensing of the atmosphere from 20 up to 120 km, a significant region where the strongest coupling between the lower and upper atmosphere occurs.

Accession Number: WOS:000502284300107

eISSN: 2072-4292

Record 43 of 362

Title: A Systematic Error Compensation Method Based on an Optimized Extreme Learning Machine for Star Sensor Image Centroid Estimation

Author(s): Wei, X (Wei, Xin); Wen, DS (Wen, Desheng); Song, ZX (Song, Zongxi); Xi, JB (Xi, Jiangbo); Zhang, WK (Zhang, Weikang); Liu, G (Liu, Gang); Li, ZX (Li, Zhixin)

Source: APPLIED SCIENCES-BASEL  Volume: 9  Issue: 22  Article Number: 4751  DOI: 10.3390/app9224751  Published: NOV 2 2019  

Abstract: As an important error in star centroid location estimation, the systematic error greatly restricts the accuracy of the three-axis attitude supplied by a star sensor. In this paper, an analytical study about the behavior of the systematic error in the center of mass (CoM) centroid estimation method under different Gaussian widths of starlight energy distribution is presented by means of frequency field analysis and numerical simulations. Subsequently, an optimized extreme learning machine (ELM) based on the bat algorithm (BA) is adopted to predict the systematic error of the actual star centroid position and then compensate the systematic error from the CoM method. In the BA-ELM model, the input weights matrix and hidden layer biases parameters are encoded as microbat's locations and optimized by utilizing the strong global search capacity of BA, which significantly improves the performance of ELM in terms of prediction accuracy. The simulation result indicates that our method can reduce the systematic error to less than 3.0 x 10(-7) pixels, and its compensation accuracy is two or three orders of magnitude higher than that of other methods for estimating a star centroid location under a 3 x 3 pixel sampling window.

Accession Number: WOS:000502570800028

Author Identifiers:

eISSN: 2076-3417

Record 44 of 362

Title: Robust contrast-transfer-function phase retrieval via flexible deep learning networks

Author(s): Bai, C (Bai, Chen); Zhou, ML (Zhou, Meiling); Min, JW (Min, Junwei); Dang, SP (Dang, Shipei); Yu, XH (Yu, Xianghua); Zhang, P (Zhang, Peng); Peng, T (Peng, Tong); Yao, BL (Yao, Baoli)

Source: OPTICS LETTERS  Volume: 44  Issue: 21  Pages: 5141-5144  DOI: 10.1364/OL.44.005141  Published: NOV 1 2019  

Abstract: By exploiting the total variation (TV) regularization scheme and the contrast transfer function (CTF), a phase map can be retrieved from single-distance coherent diffraction images via the sparsity of the investigated object. However, the CTF-TV phase retrieval algorithm often struggles in the presence of strong noise, since it is based on the traditional compressive sensing optimization problem. Here, convolutional neural networks, a powerful tool from machine learning, are used to regularize the CTF-based phase retrieval problems and improve the recovery performance. This proposed method, the CTF-Deep phase retrieval algorithm, was tested both via simulations and experiments. The results show that it is robust to noise and fast enough for high-resolution applications, such as in optical, x-ray, or terahertz imaging. (C) 2019 Optical Society of America

Accession Number: WOS:000493940500010

PubMed ID: 31674951

Author Identifiers:

ISSN: 0146-9592

eISSN: 1539-4794

Record 45 of 362

Title: Direct calculation of tightly focused field in an arbitrary plane

Author(s): Cai, YA (Cai, Yanan); Wang, ZJ (Wang, Zhaojun); Liang, YS (Liang, Yansheng); Ren, FF (Ren, Feifei); Yao, BL (Yao, Baoli); Lei, M (Lei, Ming); Yan, SH (Yan, Shaohui)

Source: OPTICS COMMUNICATIONS  Volume: 450  Pages: 329-334  DOI: 10.1016/j.optcom.2019.06.022  Published: NOV 1 2019  

Abstract: The Debye-Wolf diffraction integral is a powerful tool for computing the focused field of an illumination by a high numerical aperture (NA) objective lens. With the help of the fast Fourier Transform (FT) algorithm, this integral can be evaluated at a high processing speed. In general, the FT pair is the illumination field at the entrance pupil and the focused field in a transverse plane in the focal region, i.e., the xy-plane. To analyze the field distribution of special beams in a titled plane, conventional calculations require a stack of slices of fields in the xy-planes plane by plane. Here, we propose a modified FT-based diffraction integral algorithm that exhibits a direct FT connection between the illumination field and the field in an arbitrary plane in the focal volume. As a result, significant time saving is achieved with the proposed algorithm. The algorithm is verified by numerous simulations and should be helpful to quickly design holograms to shape complex focus used in holographic optical tweezers.

Accession Number: WOS:000477076200049

Author Identifiers:

ISSN: 0030-4018

eISSN: 1873-0310

Record 46 of 362

Title: The Lyman-alpha Solar Telescope (LST) for the ASO-S mission - II. design of LST

Author(s): Chen, B (Chen, Bo); Li, H (Li, Hui); Song, KF (Song, Ke-Fei); Guo, QF (Guo, Quan-Feng); Zhang, PJ (Zhang, Pei-Jie); He, LP (He, Ling-Ping); Dai, S (Dai, Shuang); Wang, XD (Wang, Xiao-Dong); Wang, HF (Wang, Hai-Feng); Liu, CL (Liu, Chun-Long); Zhang, HJ (Zhang, Hong-Ji); Zhang, G (Zhang, Guang); Wang, YQ (Wang, Yunqi); Liu, SJ (Liu, Shi-Jie); Zhang, HX (Zhang, Hong-Xin); Liu, L (Liu, Lei); Mao, SL (Mao, Shi-Lei); Liu, Y (Liu, Yang); Peng, JH (Peng, Jia-Hao); Wang, P (Wang, Peng); Sun, L (Sun, Liang); Han, ZW (Han, Zhen-Wei); Wang, YL (Wang, Yan-Long); Wu, K (Wu, Kun); Ding, GX (Ding, Guang-Xing); Zhou, P (Zhou, Peng); Zheng, X (Zheng, Xin); Xia, MY (Xia, Ming-Yi); Wu, QW (Wu, Qing-Wen); Xie, JJ (Xie, Jin-Jiang); Chen, Y (Chen, Ya); Song, SM (Song, Shu-Mei); Wang, H (Wang, Hong); Zhu, B (Zhu, Bo); Chu, CB (Chu, Chang-Bo); Yang, WG (Yang, Wen-Gang); Feng, L (Feng, Li); Huang, Y (Huang, Yu); Gan, WQ (Gan, Wei-Qun); Li, Y (Li, Ying); Li, JW (Li, Jing-Wei); Lu, L (Lu, Lei); Xue, JC (Xue, Jian-Chao); Ying, BL (Ying, Bei-Li); Sun, MZ (Sun, Ming-Zhe); Zhu, C (Zhu, Cheng); Bao, WM (Bao, Wei-Min); Deng, L (Deng, Lei); Yin, ZS (Yin, Zeng-Shan)

Source: RESEARCH IN ASTRONOMY AND ASTROPHYSICS  Volume: 19  Issue: 11  Article Number: 159  DOI: 10.1088/1674-4527/19/11/159  Published: NOV 2019  

Abstract: As one of the three payloads for the Advanced Space-based Solar Observatory (ASO-S) mission, the Lyman-alpha (Ly alpha) Solar Telescope (LST) is composed of three instruments: a Solar Corona Imager (SCI), a Ly alpha Solar Disk Imager (SDI) and a full-disk White-light Solar Telescope (WST). When working in-orbit, LST will simultaneously perform high-resolution imaging observations of all regions from the solar disk to the inner corona up to 2.5R(circle dot) (R-circle dot stands for the mean solar radius) with a spatial resolution of 4.8 '' and 1.2 '' for coronal and disk observations, respectively, and a temporal resolution of 30-120 s and 1-120 s for coronal and disk observations, respectively. The maximum exposure time can be up to 20 s due to precise pointing and image stabilization function. Among the three telescopes of LST, SCI is a dual-waveband coronagraph simultaneously and independently observing the inner corona in the HI Ly alpha (121.6 +/- 10nm) line and white light (WL) (700 +/- 40 nm) wavebands by using a narrowband Ly alpha beam splitter and has a field of view (FOV) from 1.1 to 2.5R(circle dot). The stray-light suppression level can attain <10(-6) B-circle dot (B-circle dot is the mean brightness of the solar disk) at 1.1R(circle dot) and <= 5x10(-8) B-circle dot at 2.5R(circle dot). SDI and WST are solar disk imagers working in the Ly alpha line and 360.0 nm wavebands, respectively, which adopt an off-axis two-mirror reflective structure with an FOV up to 1.2R(circle dot), covering the inner coronal edge area and relating to coronal imaging. We present the up-to-date design for the LST payload.

Accession Number: WOS:000507468400005

Author Identifiers:

ISSN: 1674-4527

eISSN: 2397-6209

Record 47 of 362

Title: Design of the Full-disk MagnetoGraph (FMG) onboard the ASO-S

Author(s): Deng, YY (Deng, Yuan-Yong); Zhang, HY (Zhang, Hai-Ying); Yang, JF (Yang, Jian-Feng); Li, F (Li, Fu); Lin, JB (Lin, Jia-Ben); Hou, JF (Hou, Jun-Feng); Wu, Z (Wu, Zhen); Song, Q (Song, Qian); Duan, W (Duan, Wei); Bai, XY (Bai, Xian-Yong); Wang, DG (Wang, Dong-Guang); Lv, J (Lv, Juan); Ge, W (Ge, Wei); Wang, JN (Wang, Jia-Ning); Zheng, ZY (Zheng, Zhao-Ying); Wang, CJ (Wang, Chen-Jie); Wang, NG (Wang, Nan-Ge); Ni, HK (Ni, Hou-Kun); Zeng, YZ (Zeng, Yi-Zhong); Zhang, Y (Zhang, Yang); Yang, X (Yang, Xiao); Sun, YZ (Sun, Ying-Zi); Zhang, ZY (Zhang, Zhi-Yong); Wang, XF (Wang, Xiao-Fan)

Source: RESEARCH IN ASTRONOMY AND ASTROPHYSICS  Volume: 19  Issue: 11  Article Number: 157  DOI: 10.1088/1674-4527/19/11/157  Published: NOV 2019  

Abstract: The Full-disk MagnetoGraph (FMG), a payload onboard the Advanced Space Solar Observatory (ASO-S), will measure the vector magnetic field in the photosphere. The instrument consists of a front-window filter, a telescope, an LCVR polarimeter, an image-stabilization system, a seven-stage tunable Lyot filter, a CMOS camera with 4096x4096 pixels and a pair of calibration/focus wheels. In this paper, we describe the design of the FMG instrument and provide a summary of test observations carried out with the FMG prototype.

Accession Number: WOS:000507468400003

Author Identifiers:

ISSN: 1674-4527

eISSN: 2397-6209

Record 48 of 362

Title: Advanced Space-based Solar Observatory (ASO-S): an overview

Author(s): Gan, WQ (Gan, Wei-Qun); Zhu, C (Zhu, Cheng); Deng, YY (Deng, Yuan-Yong); Li, H (Li, Hui); Su, Y (Su, Yang); Zhang, HY (Zhang, Hai-Ying); Chen, B (Chen, Bo); Zhang, Z (Zhang, Zhe); Wu, J (Wu, Jian); Deng, L (Deng, Lei); Huang, Y (Huang, Yu); Yang, JF (Yang, Jian-Feng); Cui, JJ (Cui, Ji-Jun); Chang, J (Chang, Jin); Wang, C (Wang, Chi); Wu, J (Wu, Ji); Yin, ZS (Yin, Zeng-Shan); Chen, W (Chen, Wen); Fang, C (Fang, Cheng); Yan, YH (Yan, Yi-Hua); Lin, J (Lin, Jun); Xiong, WM (Xiong, Wei-Ming); Chen, B (Chen, Bin); Bao, HC (Bao, Hai-Chao); Cao, CX (Cao, Cai-Xia); Bai, YP (Bai, Yan-Ping); Wang, T (Wang, Tao); Chen, BL (Chen, Bing-Long); Li, XY (Li, Xin-Yu); Zhang, Y (Zhang, Ye); Feng, L (Feng, Li); Su, JT (Su, Jiang-Tao); Li, Y (Li, Ying); Chen, W (Chen, Wei); Li, YP (Li, You-Ping); Su, YN (Su, Ying-Na); Wu, HY (Wu, Hai-Yan); Gu, M (Gu, Mei); Huang, L (Huang, Lei); Tang, XJ (Tang, Xue-Jun)

Source: RESEARCH IN ASTRONOMY AND ASTROPHYSICS  Volume: 19  Issue: 11  Article Number: 156  DOI: 10.1088/1674-4527/19/11/156  Published: NOV 2019  

Abstract: The Advanced Space-based Solar Observatory (ASO-S) is a mission proposed for the 25th solar maximum by the Chinese solar community. The scientific objectives are to study the relationships between the solar magnetic field, solar flares and coronal mass ejections (CMEs). Three payloads are deployed: the Full-disk vector MagnetoGraph (FMG), the Lyman-alpha Solar Telescope (LST) and the Hard X-ray Imager (HXI). ASO-S will perform the first simultaneous observations of the photospheric vector magnetic field, non-thermal imaging of solar flares, and the initiation and early propagation of CMEs on a single platform. ASO-S is scheduled to be launched into a 720 km Sun-synchronous orbit in 2022. This paper presents an overview of the mission till the end of Phase-B and the beginning of Phase-C.

Accession Number: WOS:000507468400002

Author Identifiers: