2021

• Record 373 of
  
  Title:All-optical tunable fiber filter based on a few-mode optical fiber mode interferometer coated with graphene epoxy resin composite material
  
  Author(s):Chen, Enqing(1,2); Dong, Bo(3); Li, Yang(1,2); Li, Ziwan(1,2); Wang, Xiaoli(1,2); Zhao, Yudi(1); Xu, Wei(1,2); Zhao, Wei(1,2,4); Wang, Yishan(1,2)
  Source: Optics Communications  Volume: 497  Issue:   DOI: 10.1016/j.optcom.2021.127140  Published: October 15, 2021  
  Abstract:A compact all-optical tunable fiber filter based on a few-mode optical fiber modal interferometer coated with graphene epoxy resin composite material is proposed and experimentally demonstrated. The interferometer is constructed with a 2-cm FMF connected to two single mode fibers. After coating the graphene epoxy resin composite material on the outside of the interferometer, it shows the all-optical wavelength tunability, and experimental results show that the wavelength shift changes quasilinearly with the pump power changing. The wavelength tunable range reaches 5.062 nm with a step of 0.016 nm/mw. It is expected to have practical application in optical communication, fiber sensing, fiber laser and optical spectrum analysis. © 2021 Elsevier B.V.
  Accession Number: 20212310453809
• Record 374 of
  
  Title:Genetic-algorithm-based deep neural networks for highly efficient photonic device design
  
  Author(s):Ren, Yangming(1,2); Zhang, Linxuan(1,2); Wang, Weiqiang(1,2); Wang, Xinyu(1,2); Lei, Yufang(1,2); Xue, Yulong(1,2); Sun, Xiaochen(1,2); Zhang, Wenfu(1,2)
  Source: Photonics Research  Volume: 9  Issue: 6  DOI: 10.1364/PRJ.416294  Published: June 1, 2021  
  Abstract:While deep learning has demonstrated tremendous potential for photonic device design, it often demands a large amount of labeled data to train these deep neural network models. Preparing these data requires high-resolution numerical simulations or experimental measurements and cost significant, if not prohibitive, time and resources. In this work, we present a highly efficient inverse design method that combines deep neural networks with a genetic algorithm to optimize the geometry of photonic devices in the polar coordinate system. The method requires significantly less training data compared with previous inverse design methods. We implement this method to design several ultra-compact silicon photonics devices with challenging properties including power splitters with uncommon splitting ratios, a TE mode converter, and a broadband power splitter. These devices are free of the features beyond the capability of photolithography and generally in compliance with silicon photonics fabrication design rules. © 2021 Chinese Laser Press
  Accession Number: 20212310447556
• Record 375 of
  
  Title:Secondary electron emission characteristics of the Al2O3/MgO double-layer structure prepared by atomic layer deposition
  
  Author(s):Cao, Weiwei(1,2,3); Wang, Bo(1); Yang, Yang(1); Zhu, Bingli(1,5); Guo, Junjiang(3,4,5); Xu, Peng(1,3,6); Bai, Xiaohong(1,6); Qin, Junjun(1,5); Wang, Chao(1,5); Zhu, Jingping(2); Bai, Yonglin(1,5)
  Source: Ceramics International  Volume: 47  Issue: 7  DOI: 10.1016/j.ceramint.2020.12.128  Published: April 1, 2021  
  Abstract:As a secondary electron emission layer, an Al2O3/MgO double-layer structure is fabricated by atomic layer deposition (ALD) technology. The thickness range from 1 nm to 4 nm of the top Al2O3 layer deposited on 20 nm MgO creates a double-layer. The morphology of the cross section, element distribution, surface roughness, X-ray diffraction, and secondary electron yield (SEY) values were measured by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), atomic force microscopy (AFM) and secondary electron emission (SEE) measurement systems. The SEE characteristics of the MgO single layer, Al2O3 single layer and MgO/Al2O3 double-layer were measured. The maximum SEY of a single MgO layer reached 6.2@600 eV, and the maximum SEY of a single Al2O3 layer reached 3.92@400 eV. The SEY of the Al2O3/MgO double-layer decreased when the Al2O3 thickness ranged from 1 nm to 4 nm, and the SEY reduction value of the double-layer decreased as the Al2O3 thickness increased. Finally, Dionne's semiempirical SEE model was employed to explain the SEE yield of the prepared composite film structures. These results are useful for depositing a secondary electron emission layer in the channel of microchannel plates. © 2020
  Accession Number: 20210109710602
• Record 376 of
  
  Title:Axial resolution enhancement for planar Airy beam light-sheet microscopy via the complementary beam subtraction method
  
  Author(s):Liu, Chao(1,2); Yu, Xianghua(1); Bai, Chen(1); Li, Xing(1,2); Zhou, Yuan(1,2); Yan, Shaohui(1); Min, Junwei(1); Dan, Dan(1); Li, Runze(1); Gu, Shuangyu(1,2); Yao, Baoli(1,2)
  Source: Applied Optics  Volume: 60  Issue: 32  DOI: 10.1364/AO.441070  Published: November 10, 2021  
  Abstract:Airy beam light-sheet illumination can extend the field of view (FOV) of light-sheet fluorescence microscopy due to the unique propagation properties of non-diffraction and self-acceleration.However, the side lobes create undesirable out-of-focus background, leading to poor axial resolution and low image contrast. Here, we propose an Airy complementary beam subtraction (ACBS) method to improve the axial resolution while keeping the extended FOV. By scanning the optimized designed complementary beam that has two main lobes (TML), the generated complementary light-sheet has almost identical intensity distribution to that of the planar Airy light-sheet except for the central lobe. Subtraction of the two images acquired by double exposure respectively using the planar Airy light-sheet and the planar TML light-sheet can effectively suppress the influence of the out-of-focus background. The axial resolution improves from ∼4 μm to 1.2 μm. The imaging performance was demonstrated by imaging specimens of aspergillus conidiophores and GFP labeled mouse brain section. The results show that the ACBS method enables the Airy beam light-sheet fluorescence microscopy to obtain better imaging quality. © 2021 Optical Society of America.
  Accession Number: 20214611156350
• Record 377 of
  
  Title:Intensity Demodulation Technology of FBG Time Division Multiplexing Based on Sagnac Ring
  
  Author(s):Wang, Xiaoli(1,2); Dong, Bo(1); Chen, Enqing(1,2); Li, Yang(1,2)
  Source: Guangzi Xuebao/Acta Photonica Sinica  Volume: 50  Issue: 5  DOI: 10.3788/gzxb20215005.0506003  Published: May 25, 2021  
  Abstract:A method of fiber Bragg grating time-division multiplexing intensity demodulation based on Sagnac fiber ring is presented. The time-multiplexing sensing system, consisted of the several FBG gratings with the same central-wavelength, can demodulate the signals by observing the intensity changes of the output spectrum of the FBG gratings. In the signal processing module, the wavelet analysis and Gaussian simulation algorithm are combined to demodulate the system signal together. The experimental results show that the signal-to-noise ratio of the system signal is increased by about 36% from 8.06 dB to 11.7 dB, which effectively improves the anti-interference ability of the system and the detection accuracy for the external parameters. The proposed method effectively increases the number of fiber Bragg grating sensors in the demodulation system with less cost and can be widely applied to various sensor systems or parameter detection systems. © 2021, Science Press. All right reserved.
  Accession Number: 20212510544803
• Record 378 of
  
  Title:Direct axial plane imaging of particle manipulation with nondiffracting Bessel beams
  
  Author(s):An, Sha(1,2); Peng, Tong(1,2); Yan, Shaohui(1); Zhang, Peng(1); Li, Manman(1); Yao, Baoli(1,2)
  Source: Applied Optics  Volume: 60  Issue: 11  DOI: 10.1364/AO.417854  Published: April 10, 2021  
  Abstract:Optical manipulation with nondiffracting beams has been attracting great interest and finding widespread applications in many fields such as chemistry, physics, and biomedicine. Generally, optical manipulation is conducted in an optical microscopy system, which, in general, only allows for imaging motions of particles in the transverse plane, rendering the observation of dynamics processes occurring in the axial plane impractical.We propose and demonstrate an optical manipulation system that incorporates an axial plane imaging module. With this system, the trapping behavior in the transverse plane and the transportation process in the axial plane of a particle immersed in a Bessel beamwere acquired simultaneously in real time. © 2021 Optical Society of America.
  Accession Number: 20211710263888
• Record 379 of
  
  Title:Super-resolution and optical sectioning integrated structured illumination microscopy
  
  Author(s):Dan, Dan(1); Gao, Peng(2); Zhao, Tianyu(1,3); Dang, Shipei(1,3); Qian, Jia(1,3); Lei, Ming(1); Min, Junwei(1); Yu, Xianghua(1); Yao, Baoli(1,3)
  Source: Journal of Physics D: Applied Physics  Volume: 54  Issue: 7  DOI: 10.1088/1361-6463/abc4a8  Published: February 4, 2021  
  Abstract:Super-resolution structured illumination microscopy (SR-SIM) has attracted a great deal of attention in the past few decades. As a wide-field imaging technique, SR-SIM usually suffers from issues relating to out-of-focus background, particularly when imaging thick samples. In this study, we develop an integrated SIM with simultaneous SR and optical sectioning (OS) capabilities, facilitating SR imaging of stacked optical sections, with the out-of-focus background suppressed. The combination of the merits of SR and OS is realized by means of a new image reconstruction algorithm. We confirm the validity of the integrated SIM, both experimentally and in simulation. We anticipate that this integrated SIM will assist biologists in obtaining much clearer SR images in relation to thick specimens. © 2020 IOP Publishing Ltd.
  Accession Number: 20205109635226
• Record 380 of
  
  Title:Dark matter-wave gap solitons of Bose-Einstein condensates trapped in optical lattices with competing cubic-quintic nonlinearities
  
  Author(s):Chen, Junbo(1,2); Zeng, Jianhua(1,2)
  Source: Chaos, Solitons and Fractals  Volume: 150  Issue:   DOI: 10.1016/j.chaos.2021.111149  Published: September 2021  
  Abstract:Solitons are nonlinear self-sustained wave excitations and probably among the most interesting and exciting emergent nonlinear phenomenon in the corresponding theoretical settings. Bright solitons with sharp peak and dark solitons with central notch have been well known and observed in various nonlinear systems. The interplay of periodic potentials, like photonic crystals and lattices in optics and optical lattices in ultracold atoms, with the dispersion has brought about gap solitons within the finite band gaps of the underlying linear Bloch-wave spectrum and, particularly, the bright gap solitons have been experimentally observed in these nonlinear periodic systems, while little is known about the underlying physics of dark gap solitons. Here, we theoretically and numerically investigate the existence, property and stability of one-dimensional matter-wave gap solitons and soliton clusters of Bose-Einstein condensates trapped in optical lattices with competing cubic-quintic nonlinearity, the higher-order of which is self-defocusing and the lower-order (cubic) one is chosen as self-defocusing or focusing nonlinearities. By means of the conventional linear-stability analysis and direct numerical calculations with initial perturbations, we identify the stability and instability areas of the corresponding dark gap solitons and clusters ones. © 2021 Elsevier Ltd
  Accession Number: 20212610567802
• Record 381 of
  
  Title:Design and Modulation Performance of Ultrafast Light-controlled Pulsed X-ray Tube with Photocathode
  
  Author(s):Xuan, Hao(1,2); Liu, Yongan(1); Qiang, Pengfei(1); Su, Tong(1); Yang, Xianghui(1); Sheng, Lizhi(1); Zhao, Baosheng(1)
  Source: Guangzi Xuebao/Acta Photonica Sinica  Volume: 50  Issue: 7  DOI: 10.3788/gzxb20215007.0725001  Published: July 25, 2021  
  Abstract:In order to solve the easy-broken structure, low energy efficiency and heat dissipation of the traditional X-ray tube with filament based on thermionic cathode, a novel light-controlled pulsed X-ray tube device is deostrated in this paper. By matching the parameters of photocathode and light source, S20 cathode with high quantum efficiency and LED with 460 nm wavelength were selected. At the same time, the overall structure design of the X-ray tube is determined by the simulation. Finally, the maximum tube current of 2.37 mA is realized, the electron emission efficiency of photocathode is 0.288 mA/lm, and the output X-ray energy is adjustable from 0 to 25 keV. In addition, based on the characteristics of easy-access to be modulated of the light-controlled pulsed X-ray tube, different frequencies input signal restoration experiment and arbitrary contor X-ray restoration experiment was carried out. © 2021, Science Press. All right reserved.
  Accession Number: 20213110707042
• Record 382 of
  
  Title:Development Current Status and Trend Analysis of Satellite Laser Communication(Invited)
  
  Author(s):Gao, Duorui(1,2,3); Xie, Zhuang(1,2,3); Ma, Rong(1,2,3); Wang, Wei(1,2); Bai, Zhaofeng(1,2); Jia, Shuaiwei(1,2,3); Shao, Wen(1,2,3); Xie, Xiaoping(1,2,3)
  Source: Guangzi Xuebao/Acta Photonica Sinica  Volume: 50  Issue: 4  DOI: 10.3788/gzxb20215004.0406001  Published: April 25, 2021  
  Abstract:Satellite laser communication, with its wide bandwidth and no electromagnetic spectrum constraints, has become an effective means to solve the bandwidth bottleneck of satellite microwave communication, alleviate the shortage of satellite spectrum resources and realize high-speed satellite communication. This paper introduces the system composition and characteristics of satellite laser communication, and analyzes the development context, latest progress and future development plans of satellite laser communication technology at international and domestic. Combined with the requirements of future space network and deep-space exploration, this paper summarizes from five aspects of high-speed, deep-space, integration, networking and all-optical, and discusses the key technologies involved in the future, which can provide reference for the research of satellite laser communication technology in China. © 2021, Science Press. All right reserved.
  Accession Number: 20212010360135
• Record 383 of
  
  Title:Monolithic RGB Micro-Light-Emitting Diodes Fabricated with Quantum Dots Embedded inside Nanoporous GaN
  
  Author(s):Song, Jie(1); Kang, Jin-Ho(2); Han, Jung(2)
  Source: ACS Applied Electronic Materials  Volume: 3  Issue: 11  DOI: 10.1021/acsaelm.1c00700  Published: November 23, 2021  
  Abstract:We report the use of colloidal quantum dots (QDs) embedded in nanoporous (NP) gallium nitride (GaN) as a color converter to achieve different emission colors and fabricate micro-light-emitting diodes (micro-LEDs). The optical property of NP-GaN has been studied by analyzing the light transmittance propagating in NP-GaN. A strong light scattering effect can be induced by NP-GaN, resulting in a dramatically increased optical transmission path for blue light and high light absorption by QDs loaded inside NP-GaN. A 4 in. color converter has been achieved with a wavelength deviation of 1 nm across the entire wafer. Monolithic red, green, and blue micro-LEDs have been fabricated with a pixel size of around 35 × 35 μm2. ©
  Accession Number: 20214611148360
• Record 384 of
  
  Title:Collective multipartite Einstein-Podolsky-Rosen steering via cascaded four-wave mixing of rubidium atoms
  
  Author(s):Liu, Yang(1,2,3); Cai, Yin(1); Luo, Binshuo(1); Yan, Jin(1); Niu, Mengqi(1); Li, Feng(1); Zhang, Yanpeng(1)
  Source: Physical Review A  Volume: 104  Issue: 3  DOI: 10.1103/PhysRevA.104.033704  Published: September 2021  
  Abstract:Collective multipartite Einstein-Podolsky-Rosen (EPR) steering is a type of quantum correlation shared among n parties, where the EPR paradox of one party can be realized only by performing local measurements on all the remaining n-1 parties. Here, we propose an efficient method to produce collective multipartite EPR steering via symmetrically and asymmetrically cascading parametric amplification processes, i.e., four-wave mixing (FWM) of rubidium atoms. The simplified collective-steering criterion is introduced using the Coffman-Kundu-Wootters monogamy relation. Moreover, by actively adjusting the parametric gains, the collective EPR steerability is optimized in our schemes. We find that the scale of collective steering can be extended by cascading more FWMs; in particular, introducing optical loss is useful for generating collective steering with more parties only in the asymmetry structure. Our results pave the way for the construction of quantum networks and provide a promising candidate for one-sided device-independent quantum cryptography among multiple users. © 2021 American Physical Society.
  Accession Number: 20213810900937