2017

• Record 529 of
  
  Title:Optofluidic in-fiber interferometer based on hollow optical fiber with two cores
  
  Author(s):Yuan, Tingting(1); Yang, Xinghua(1); Liu, Zhihai(1,2); Yang, Jun(1); Li, Song(1); Kong, Depeng(3); Qi, Xiuxiu(1); Yu, Wenting(1); Long, Qunlong(1); Yuan, Libo(1)
  Source: Optics Express  Volume: 25  Issue: 15  DOI: 10.1364/OE.25.018205  Published: July 24, 2017  
  Abstract:We demonstrate a novel integrated optical fiber interferometer for in-fiber optofluidic detection. It is composed of a specially designed hollow optical fiber with a micro-channel and two cores. One core on the inner surface of the micro-channel is served as sensing arm and the other core in the annular cladding is served as reference arm. Fusion-and-tapering method is employed to couple light from a single mode fiber to the hollow optical fiber in this device. Sampling is realized by side opening a microhole on the surface of the hollow optical fiber. Under differential pressure between the end of the hollow fiber and the microhole, the liquids can form steady microflows in the micro-channel. Simultaneously, the interference spectrum of the interferometer device shifts with the variation of the concentration of the microfluid in the channel. The optofluidic in-fiber interferometer has a sensitivity of refractive index around 2508 nm/RIU for NaCl. For medicine concentration detection, its sensitivity is 0.076 nm/mmolL−1 for ascorbic acid. Significantly, this work presents a compact microfluidic in-fiber interferometer with a micro-channel which can be integrated with chip devices without spatial optical coupling and without complex manufacturing procedure of the waveguide on the chips. © 2017 Optical Society of America.
  Accession Number: 20173003982850
• Record 530 of
  
  Title:The test and analysis on pulse signal detection abilities of the X-ray detector MCP for pulsar navigation
  
  Author(s):Zhou, Qingyong(1,2,3); Sheng, Lizhi(4); Wei, Ziqing(2,3); Liu, Siwei(2,3); Jiang, Kun(5); Chen, Chun(4); Ji, Jianfeng(2,3); Ren, Hongfei(2,3); Ma, Gaofeng(1)
  Source: Lecture Notes in Electrical Engineering  Volume: 438  Issue:   DOI: 10.1007/978-981-10-4591-2_51  Published: 2017  
  Abstract:The Micro-Channel Plate detector (MCP) is an X-ray detecting system with a mature technology, which is suitable for space observation and navigation application of X-ray pulsar. For analyzing the X-ray pulse signal observation capability of MCP detector, a long-time experiment of MCP detector with different radiation flux and different background noise were carried out by the ground testing system. Meanwhile, a set of evaluation methods of the pulse observation capability of X-ray detector was established, those expressions of the signal-to-noise ratio (SNR), the correlation of pulse profile (R), the accuracy of pulse time of arrival (σTOA), the minimum detectable power (Pmin) are derived from the photon counting model of the ground testing system. In the whole testing experiment which took almost a week, 8 groups of 10000 s X-ray photon TOAs dataset were received by the 20 cm2 MCP detectors, the best periods were searched and gained, the observable pulse profiles were replicated, those characteristic parameters of pulse profile were estimated. The result of this experiment shows that the MCP detector has a good capability of X-ray pulse signal observation and reconstruction, the SNR, R, σTOA of the observed pulse profile at the low pulse signal flux (fp = 0:05 ph/cm2/s) are (35.73, 88.38%, 51.53 µs) and are (35.73, 88.38%, 51.53 µs) at strong background noise (B = 16), so, the MCP detector has a good observation ability of a certain faint X ray pulsar. The result also has revealed that the minimum detectable power (Pmin) of MCP detector is closely related to the power intensity of the X-ray pulsar simulator, is less correlation with the intensity of background noise. The Pmin has the minimal value which is also called the minimum detectable cutoff power. When the X-ray pulse signal received by MCP detector is weak, Pmin is close to its minimal value (1 × 10-14 W). © Springer Nature Singapore Pte Ltd. 2017.
  Accession Number: 20172003680384
• Record 531 of
  
  Title:Entanglement generation with integrated optical frequency comb sources
  
  Author(s):Reimer, Christian(1); Kues, Michael(1,2); Roztocki, Piotr(1); Wetzel, Benjamin(1,3); Bromberg, Yaron(4); Little, Brent E.(5); Chu, Sai T.(6); Moss, David J.(7); Caspani, Lucia(8); Morandotti, Roberto(1)
  Source: Optics InfoBase Conference Papers  Volume: Part F54-NLO 2017  Issue:   DOI: 10.1364/NLO.2017.NM1A.5  Published: 2017  
  Abstract:We show that integrated optical frequency comb sources, based on on-chip microring resonators, can be used as versatile sources of two- and multi-photon entangled states when operated well below their optical parametric oscillation threshold. © OSA 2017.
  Accession Number: 20173504083027
• Record 532 of
  
  Title:On-chip quantum state generation by means of integrated frequency combs
  
  Author(s):Sciara, Stefania(1,2); Kues, Michael(1,3); Reimer, Christian(1); Roztocki, Piotr(1); Wetzel, Benjamin(1,4); Bromberg, Yaron(5); Little, Brent E.(6); Chu, Sai T.(7); Moss, David J.(8); Caspani, Lucia(9); Morandotti, Roberto(1)
  Source: Summer Topicals Meeting Series, SUM 2017  Volume:   Issue:   DOI: 10.1109/PHOSST.2017.8012710  Published: August 17, 2017  
  Abstract:Entangled photon-pair sources are key building blocks towards the realization of applications in quantum information processing [1], quantum communications [2], as well as imaging and sensing with resolutions exceeding the classical limit [3]. The generation of, e.g. polarization, time-energy and time-bin entangled photon-pairs has been demonstrated using spontaneous parametric down-conversion (SPDC) in nonlinear second-order media, as well as spontaneous four-wave mixing (SFWM) in third-order nonlinear media. Specifically, nonlinear (third-order) interactions in on-chip microring resonators have been widely used to achieve classical frequency combs [4], mode-lock lasers [5], signal processing [6], etc. Integrated photonics can also find applications for quantum state generation in compact, scalable and efficient devices, required for future optical quantum circuits. In particular, solutions focusing on an integrated (on-chip) approach have been recently investigated and developed, including integrated quantum circuits, sources and detectors [7]. In contrast to waveguides, microring resonators [8] with narrow resonances and high Q-factors, offer an improvement in photon-pair generation efficiency, as well as a narrow photon-pair bandwidth, making them compatible with quantum optical devices (e.g. high temporal-resolution single-photon detectors and quantum memories). Most importantly, in contrast to non-resonant waveguides, where individuals photon-pairs, featured by one signal/idler frequency pair, are generally produced, resonant nonlinear cavities (e.g., microring resonators) allow the generation of correlated photon-pairs on multiple signal/idler frequency channels [9], due to their periodic and equidistant resonance structure. © 2017 IEEE.
  Accession Number: 20173804168577
• Record 533 of
  
  Title:Transmission performance of 90°-bend optical waveguides fabricated in fused silica by femtosecond laser inscription
  
  Author(s):Lv, Jing(1,2); Bai, Jing(2); Zhou, Kaiming(2,3); Mei, Xuesong(1); Wang, Kedian(1); Li, Ming(1,2); Cheng, Guanghua(2)
  Source: Optics Letters  Volume: 42  Issue: 17  DOI: 10.1364/OL.42.003470  Published: September 1, 2017  
  Abstract:The L-shape waveguide was written in fused silica using a femtosecond laser with beam shaping. The guiding structure supports good light turning; 0.88 dB/turn was achieved at the silica-air interface. By using the finite-different time-domain method, the turn loss due to the turning structure and refractive index of the L-shape waveguide has been simulated. The results show that the proposed method has unprecedented flexibility in fabricating a 90°-bend waveguide. © 2017 Optical Society of America.
  Accession Number: 20173604120668
• Record 534 of
  
  Title:Eight-wave mixing parametrical amplification
  
  Author(s):Liu, Yang(1,3); Li, Kangkang(2); Liu, Yize(2); Yang, Gaoguo(2); Wang, Kun(2); Zhang, Yanpeng(2)
  Source: Optics Express  Volume: 25  Issue: 21  DOI: 10.1364/OE.25.025212  Published: October 16, 2017  
  Abstract:We investigate parametrically amplified eight-wave mixing (PA-EWM). The double dressed PA-four-wave mixing (PA-FWM) is the superposition of one PA-FWM process, two different PA-six-wave mixing (PA-SWM) processes (PA-SWM1 and PA-SWM2 with external dressing field 776nm and 795nm, respectively) and one PA-EWM process. When the phases among FWM, SWM1, SWM2 and EWM change from 0 to π, the double dressed PA-FWM could gradually satisfy the pure enhancement (all 0), partial enhancement and suppression (mixture of 0 and π), or pure suppression condition (all π). The outcomes of the investigation can potentially contribute to the development of multi-channel quantum information processing and high dimensional stereoscopic imaging. © 2017 Optical Society of America.
  Accession Number: 20174204282385
• Record 535 of
  
  Title:Pulsed quantum frequency combs from an actively mode-locked intra-cavity generation scheme
  
  Author(s):Roztocki, Piotr(1); Kues, Michael(1,2); Reimer, Christian(1); Wetzel, Benjamin(1,3); Little, Brent E.(4); Chu, Sai T.(5); Moss, David J.(1,6); Morandotti, Roberto(1,7,8)
  Source: Optics InfoBase Conference Papers  Volume: Part F82-CLEO_Europe 2017  Issue:   DOI: 10.1109/cleoe-eqec.2017.8086465  Published: 2017  
  Abstract:null
  Accession Number: 20180104611882
• Record 536 of
  
  Title:Type II microcomb generation in a filter-driven four wave mixing laser
  
  Author(s):Cooper, Andrew(1); Bao, Hualong(1); Chu, Sai T.(2); Moss, Dave J.(3); Morandotti, Roberto(4); Little, Brent E.(5); Peccianti, Marco(1); Pasquazi, Alessia(1)
  Source: Optics InfoBase Conference Papers  Volume: Part F82-CLEO_Europe 2017  Issue:   DOI:   Published: 2017  
  Abstract:null
  Accession Number: 20180104611884
• Record 537 of
  
  Title:How to obtain a shortest mode converter based on periodic waveguide with limited index contrast?
  
  Author(s):Zhang, Lingxuan(1,2,3); Zhang, Wenfu(1,2,3); Wang, Guoxi(1,2,3); Hu, Yaowei(1); Ge, Zhiqiang(1,2,3); Wang, Leiran(1,2,3); Sun, Qibing(1,2); Wang, Weiqiang(1,2,3); Gong, Yongkang(2,4); Zhao, Wei(1,2,3)
  Source: Applied Physics B: Lasers and Optics  Volume: 123  Issue: 5  DOI: 10.1007/s00340-017-6718-7  Published: May 1, 2017  
  Abstract:Mode converter is one of most significant elements in photonic integrated circuits. It relies on increasing index contrast to shorten its length. However, index contrast is limited for technology. In addition, an overlarge index contrast leads to some disadvantages, such as large scattering loss, reflection loss, and small tolerance for manufacturing. Thus, an approximate scheme to design a mode converter is manipulating the transverse distribution of index to achieve the minimum length when the index contrast is given. We have analytically deduced the theoretical maximum coupled efficiency in periodic waveguide, which determines the minimum coupling length of mode converter. What is more, we have demonstrated how to construct a distribution function of indices in a cross section of waveguide to achieve the minimum length and a case is also given to illustrate the process. Proofs, based on both mathematic derivation and numerical simulation, have been exhibited in the paper. © 2017, Springer-Verlag Berlin Heidelberg.
  Accession Number: 20171603582040
• Record 538 of
  
  Title:In-line Mach-zehnder interferometer with D-shaped fiber grating for curvature and temperature measurement
  
  Author(s):Jiang, Biqiang(1,2); Bai, Zhiyong(2); Wang, Changle(2); Zhao, Yunhe(2); Zhou, Kaiming(2,3); Zhang, Lin(2)
  Source: Proceedings of SPIE - The International Society for Optical Engineering  Volume: 10604  Issue:   DOI:   Published: 2017  
  Abstract:A sensing configuration is implemented by using a fiber Mach-Zehnder interferometerwith D-shaped fiber Bragg grating for simultaneous measurement of curvature and temperature.The results show a curvature sensitivity of maximum 87.7 nm/m-1 © 2017 SPIE. All rights reserved.
  Accession Number: 20195207916998
• Record 539 of
  
  Title:Temperature-calibrated high-precision refractometer using a tilted fiber Bragg grating
  
  Author(s):Jiang, Biqiang(1,2); Zhou, Kaiming(2,3); Wang, Changle(2); Zhao, Yunhe(2); Zhao, Jianlin(1); Zhang, Lin(2)
  Source: Optics Express  Volume: 25  Issue: 21  DOI: 10.1364/OE.25.025910  Published: October 16, 2017  
  Abstract:We present a refractometer with main- and vernier-scale to measure the refractive index (RI) of liquids with high precision by using the fine spectrum structure of a tilted fiber Bragg grating (TFBG). The absolute RI values are determined by the accurate wavelength of cut-off mode resonances. The main- and vernier-scale are calibrated by measuring large groups of fine spectra at different cut-off mode resonances in a small RI range, and the use of vernier-scale certainly reduces the RI measurement uncertainty resulted from the discrete cladding mode resonances. The performance of the TFBG-based vernier refractometer is experimentally verified by exploring the temperature dependence of RI of anhydrous ethanol in a near infrared region, showing an enhanced accuracy to the order of 10−4, high repeatability and temperature self-calibration capability. © 2017 Optical Society of America.
  Accession Number: 20174304313456
• Record 540 of
  
  Title:Vignetting effect in Fourier ptychographic microscopy
  
  Author(s):An, P.A.N.(1,2); Chao, Z.U.O.(3); Yuege, X.I.E.(4); Zhang, Yan(1,2); Ming, L.E.I.(1); Baoli, Y.A.O.(1)
  Source: arXiv  Volume:   Issue:   DOI:   Published: October 18, 2017  
  Abstract:Fourier ptychographic microscopy (FPM) is a computational imaging technique that overcomes the physical space-bandwidth product (SBP) limit of a conventional microscope by applying angular diversity illuminations. In the usual model of FPM, the microscopic system is approximated by being taken as space-invariant with transfer function determined by a complex pupil function of the objective. However, in real experimental conditions, several unexpected "semi-bright and semi-dark" images with strong vignetting effect can be easily observed when the sample is illuminated by the LED within the "transition zone" between bright field and dark field. These imperfect images, apparently, are not coincident with the space-invariant model and could deteriorate the reconstruction quality severely. In this Letter, we examine the impact of this space-invariant approximation on FPM image formation based on ray-based and rigorous wave optics-based analysis. Our analysis shows that for a practical FPM microscope with a low power objective and a large field of view, the space invariance is destroyed by diffraction at other stops associated with different lens elements to a large extent. A modified version of the space-variant model is derived and discussed. Two simple countermeasures are also presented and experimentally verified to bypass or partially alleviate the vignetting-induced reconstruction artifacts. © 2017 Optical Society of America Copyright © 2017, The Authors. All rights reserved.
  Accession Number: 20200302522