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Record 385 of
Title:Dependence of field splitting characteristics on metallic components topological configuration in multilaminar plasmonic films
Author(s):Kang, Yifan(1,2,3); Yang, Hongtao(1); Wang, Chao(4); Li, Yongfeng(5); Cao, Weiwei(1)
Source: IEEE Transactions on Nanotechnology Volume: 20 Issue: DOI: 10.1109/TNANO.2021.3112704 Published: 2021
Abstract:The dependence of field splitting characteristics of multilaminar plasmonic structure on its metallic components topology is analyzed. It is found that the coupling interaction between metallic-particle-centered localized surface plasmons generates a collective effect, collective metallic-particles-centered plasmons, to dominantly determine the plasmonic resonances of the structure. When the metallic particles filling ratio within the matrix is high, this collective effect may cause resonance splitting phenomenon and greatly enlarge the frequency range of field splitting enhancement, which is the physical mechanism and also the designing guideline for multilaminar plasmonic broadband perfect absorber. The surface plasmon polaritons are concurrently superimposed on the metallic-particles-centered collective effect to establish an inter-group coupling competition effect, which may strengthen or weaken the preexisting resonance processes through constructive or destructive field interference in between. This serves as the theoretical base for narrowband field splitting enhancement applications. Moreover, we have revealed the existence of the corresponding relationship between the specific field splitting resonance and those participating or dominating metallic particles involved, which provides the advantages to finely tailor field splitting characteristics through precise implantation of nanoparticles. ? 2021 IEEE.
Accession Number: 20213810925184
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Record 386 of
Title:Modeling and simulation analysis of a non-line-of-sight infrared laser imaging system
Author(s):Tan, Jingjing(1,2); Su, Xiuqin(1); Wang, Kaidi(1,2); Wu, Jingyao(1,2)
Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 11761 Issue: DOI: 10.1117/12.2585336 Published: 2021
Abstract:Non-line-of-sight (NLOS) imaging technology is to a€ see' the target out of sight, such as an object around a corner or hidden by some shelters. However, due to constraints of device definition and computing load, NLOS system is usually expensive and requires hidden objects with special material and simple shape. Besides, imaging space of system is limited. We perform a series of simulation with 1550nm infrared laser to expand the application field and improve the performance of NLOS system. Based on math and physical properties, main experimental components are modeled and data acquisition process is completed first. Then, the ellipsoid inversion algorithm is used to reconstruct the hidden space and imaging results are obtained. Finally, multiple series of system parameters are set and their influence on imaging results is analyzed. Results demonstrate that echo signal intensity after multiple reflections provides adequate information to reconstruct the geometry of a hidden object. However, the number of laser scanning position, resolution of detector, voxel division and location of the scanning area will all have a critical influence on NLOS imaging results. ? COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.
Accession Number: 20210509874607
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Record 387 of
Title:High-side mode suppression ratio with a high-stability external-cavity diode laser array at 976 nm in a wide temperature and current range
Author(s):Liu, Bin(1,2,3); Liu, Hui(1); Zhu, Pengfei(3); Liu, Xingsheng(3)
Source: Optics Communications Volume: 486 Issue: DOI: 10.1016/j.optcom.2021.126792 Published: May 1, 2021
Abstract:A high-side mode suppression ratio (SMSR) and high-stability external-cavity diode laser array employing optical feedback from a volume Bragg grating (VBG) with 15% diffraction efficiency at 976 nm was investigated. Based on the transfer matrix method and on the multimode rate equation, the theoretical model for an external-cavity diode laser at 976 nm was built for different temperature and current values. Both the simulated and the experimental results show that the temperature and the current range of such laser array with a front end reflectivity (Rf) of 0.5% are 10 °C and 15 A broader than that for an external cavity with Rf = 2%. As a result, the external-cavity diode laser array at 976 nm with a Rf value of 0.5% exhibits a high stability in the temperature range of 15–35 °C and from 15 to 50 A. Moreover, it shows an SMSR higher than 30 dB and a power larger than 33.9 W at 50A. ? 2021 Elsevier B.V.
Accession Number: 20210409817755
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Record 388 of
Title:Ultrafast photonics applications of zirconium carbide as a novel mode-locker for fiber lasers
Author(s):Liu, Sicong(1); Lv, Ruidong(1,2); Wang, Jiang(1,3); Wang, Yishan(4); Wang, Hushan(4); Zhang, Han(5); Wang, Yonggang(1)
Source: Journal of Materials Chemistry C Volume: 9 Issue: 47 DOI: 10.1039/d1tc04073a Published: December 21, 2021
Abstract:Zirconium carbide (ZrC), as a novel member of the MXene family, has outstanding physical and chemical properties; however, the applications of ZrC in ultrafast photonics are still rare. Herein, a ZrC film was deposited by magnetron sputtering deposition (MSD) technology onto a D-shaped fiber and the nonlinear optical properties of the ZrC film were demonstrated. MSD technology is an advanced preparation method applicable to various materials. The saturation intensity and the modulation depth of the ZrC film were measured to be 197.6 MW cm-2 and 11.9%, respectively. After inserting the ZrC SA into an erbium-doped fiber laser (EDFL) cavity, a passive mode-locked EDFL pulse was formed. In mode-locked operation, conventional solitons with an ultrashort pulse duration of 395 fs and an output power of 49.86 mW were achieved in the communication band. The corresponding central wavelength of the output spectrum was 1562.19 nm with a 7.73 nm spectral width. This work pioneers the application of a ZrC-based device as a mode-locker to achieve ultrashort pulses for the first time and expands the application of the ZrC material. The experimental results open new opportunities for the use of ZrC in mode-locked lasers and photonics applications. This journal is ? The Royal Society of Chemistry.
Accession Number: 20215111331131
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Record 389 of
Title:A synchroscan streak tube with high deflection sensitivity
Author(s):Liu, Xue-Ling(1,2); Tian, Jin-Shou(1,4); Tian, Li-Ping(3); Chen, Ping(1); Zhang, Min-Rui(1); Xue, Yan-Hua(1); Li, Ya-Hui(1,2); Fang, Yu-Man(1,2); Xu, Xiang-Yan(1); Liu, Bai-Yu(1); Gou, Yong-Sheng(1)
Source: Wuli Xuebao/Acta Physica Sinica Volume: 70 Issue: 21 DOI: 10.7498/aps.70.20210814 Published: November 2021
Abstract:A synchroscan streak tube with high spatiotemporal resolution and high deflection sensitivity is proposed, which contains several innovation designs. Some measures are taken to improve the imaging performances of the streak tube. Firstly, in order to obtain a high deflection sensitivity, the difference in voltage between the photocathode and anode and the length of the equipotential region of the streak tube are reduced as much as possible. Secondly, by introducing a hyperfine grid behind the cathode, reasonably designing the voltages applied to the six-electrode electrostatic focusing system, and moving the electron beam crossing point to the entrance of the deflection plates, the temporal dispersion and the temporal distortion of the streak tube are reduced, and the spatiotemporal resolution of the streak tube is improved. Besides, the streak tube is technically analyzed by tracking the temporal and spatial distribution of electrons under an operating voltage of 7000 V with the aid of computer simulation technology (CST) software. The results show that the deflection sensitivity is 125 mm/kV, the physical temporal resolution is better than 1.83 ps @MTF = 10%, and the static spatial resolution on the photocathode is better than 38 lp/mm @MTF = 10% over the effective photocathode area with a size of 10 mm × 4 mm. By applying a synchronous scanning voltage with a repetition frequency of 250 MHz to the deflection electrode, the results show that the dynamic spatial resolution of the streak tube is better than 16 lp/mm, the limit of the dynamic temporal resolution is 1.39 ps, and two rectangular electron pulses with a size of 10 mm × 20 μm and an interval of 2.3 ps emitted from the photocathode can be well resolved by the streak tube. In addition, the experimental measurements are conducted with a streak tube developed in our laboratory. The results demonstrate that the photocathode of the streak tube can work in the entire visible light region, and the response in the short wavelength region is significantly better than that in the long wavelength region. The static spatial resolution of this streak tube is 40 lp/mm in the center of the photocathode. The temporal resolution of this streak tube is 5.55 ps measured under a synchronous scanning voltage with a repetition frequency of 75 MHz. ? 2021 Chinese Physical Society.
Accession Number: 20214911292651
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Record 390 of
Title:Lensless multimode fiber imaging based on wavefront shaping
Author(s):Zhang, Zaikun(1,2,3,4); Kong, Depeng(3); Geng, Yi(1,2,3); Chen, Hui(1,2,3); Wang, Ruiduo(1,2,3); Da, Zhengshang(4); He, Zhengquan(3)
Source: Applied Physics Express Volume: 14 Issue: 9 DOI: 10.35848/1882-0786/ac19d4 Published: September 2021
Abstract:In this letter, we proposed a compact multimode fiber (MMF)-based laser scanning endoscope (LSE) using wavefront shaping with a liquid crystal spatial light modulator. Experimentally, we demonstrated the lensless imaging capability of the LSE using a negative USAF-1951 test target placed near the distal MMF facet, obtaining ~7000-pixel images with micro-level spatial resolution and high contrast across a 105 μm field of view. This study proves the feasibility of a single MMF imaging without mechanical scanning, and also paves the way for ultra-thin micro-endoscopic imaging. ? 2021 The Japan Society of Applied Physics.
Accession Number: 20213410811243
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Record 391 of
Title:Terahertz signatures and quantitative analysis of glucose anhydrate and monohydrate mixture
Author(s):Yan, Hui(1,2,3); Fan, Wenhui(1,3,4); Chen, Xu(1); Liu, Lutao(1,3); Wang, Hanqi(1,3); Jiang, Xiaoqiang(1,3)
Source: Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy Volume: 258 Issue: DOI: 10.1016/j.saa.2021.119825 Published: September 5, 2021
Abstract:Glucose, as the main energy carrier and significant source of nutrition, generally comes in two available forms of anhydrate and monohydrate in commercial production. Considering their respective application occasions, proper identification of glucose in single composition or binary-mixture and quantification of the mixture are crucial in industry monitoring to guarantee merchandise quality. Simultaneously, public confusions of glucose are rather ubiquitous partly due to anhydrate and monohydrate with identical white crystalline appearance. In this paper, utilizing the molecular fingerprints of terahertz (THz) technology that are corresponding to structural characteristics of anhydrous and hydrated form, THz signatures of glucose anhydrate, monohydrate and their mixture, as well as THz spectral transformation from monohydrate to anhydrate with the dehydrating process are systematically studied. Some visible peaks of monohydrate were noted at 1.82 and 1.99 THz signifying the presence of hydrated structure. However, with the dehydrating process, the peaks related to the hydrated structure are not very apparent when the peaks at 1.44 and 2.08 THz appear due to changes in the molecular structure of anhydrate, which provide clear indication for hydrogen-bond network reconstruction at the micro level. Furthermore, characteristic peaks at 1.44 and 1.82 THz can be specified as the main quantitative indicators for quantitative detection. The linear relationships between the amplitudes of characteristic peaks and the percentage compositions of anhydrate and monohydrate are revealed. Three commercially available brands of edible glucose powder A, B, C were effectively identified by THz signatures. While powder C was recognized as binary-mixture and the proportion of anhydrate and monohydrate was further quantified. THz spectroscopy technology has advantages of direct recognition, simple quantitative model based on THz absorption peaks, and no need for complicated chemical treatment. It may be potentially shed light on industrial monitoring of glucose production and other related mixture in the future. ? 2021 Elsevier B.V.
Accession Number: 20211710255916
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Record 392 of
Title:Large field of view 3D detection with a bionic curved compound-eye camera
Author(s):Liu, Jinheng(1,2); Zhang, Yuanjie(1,2); Xu, Huangrong(1,2); Yu, Weixing(1,2)
Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 12065 Issue: DOI: 10.1117/12.2605594 Published: 2021
Abstract:In the bionic curved compound-eye camera (BCCEC) we have invented, the overlapping field of view (FOV) among the ommatidia makes 3D detection possible. In this work, we analyzed the overlapping FOV in BCCEC in detail to prove its potential in 3D detection and designed a new experiment to test its performance. In that the FOVs of multiple ommatidia in BCCEC overlap each other, the FOV of a single ommatidium is used as a representative analysis. The relationship between the overlapping ratio of FOV and the object distance is quantitatively calculated. The results show that more than 95% of the FOV can be 3D reconstructed when the object distance exceeds 32 cm. Next, in order to realize the automatic calibration of all ommatidia, ommatidia are numbered and an addressing algorithm based on the number information of ommatidia is designed, which can be used to determine the adjacent ommatidia of any ommatidium so as to acquire the ommatidia pairs that need to be calibrated. Then, since the aperture of ommatidium is relatively small and it is difficult to accurately align, a new 3D detection experiment is designed. The laser rangefinder is fixed, the black paper is used to block the laser and the formed light spot is used as the detection target. The experimental results show that 3D detection can be performed in the whole FOV of BCCEC. The BCCEC can obtain multi-dimensional information in a large FOV, and it have greater application potential in obstacle avoidance and navigation. ? 2021 SPIE.
Accession Number: 20220211438097
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Record 393 of
Title:Analysis on effect of filling glue between the frame and lens with small aperture
Author(s):Song, Yang(1); Ye, Jing(1,2); Chai, Wenyi(1); Chu, Nanqing(1,2); Xu, Yang(1); Hu, Yongming(1)
Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 11761 Issue: DOI: 10.1117/12.2584978 Published: 2021
Abstract:There are different kinds of mirror in the space instrument. Sometimes, engineers use filling glue to fill the small gap of the lens and its frame. Thus the structure may be more stable. However, this kind of method could also bring some new problems. Because of different thermal expansion coefficient of the lens and frame, the thermal deformation may be different during the temperature change, which will affect the surface accuracy of the lens and the vibration response. The thickness of glue block and the distributed form of the glue are the key factors. The paper focused on these factors and did some simulations to find out how these factors affect the surface accuracy and fundamental frequency. Then, the paper gave some proposals on this issue. ? COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.
Accession Number: 20210509874606
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Record 394 of
Title:Dark matter-wave gap solitons in dense ultracold atoms trapped by a one-dimensional optical lattice
Author(s):Li, Jiawei(1,2,3); Zeng, Jianhua(1,3)
Source: Physical Review A Volume: 103 Issue: 1 DOI: 10.1103/PhysRevA.103.013320 Published: January 2021
Abstract:Optical lattices have been used as a versatile toolbox to control Bose-Einstein condensates (BECs) in recent years, and a wealth of emergent nonlinear phenomena have been found, including bright gap solitons and dark ones, among which the former has been realized in experiments. The latter, however, has only theoretical results and its fundamental properties are still not well understood. Here we theoretically and numerically explore an open issue of creating stable matter-wave dark gap solitons in a one-dimensional optical lattice, onto which the BECs with self-defocusing quintic nonlinearity are loaded. Using linear-stability analysis and direct simulations, the formation, structures, and properties of dark gap solitons in quintic nonlinearity have been compared to those upheld by cubic Kerr nonlinearity. In particular, we uncover that the dark gap solitons and soliton clusters are robustly stable in the first finite band gap of the underlying linear spectrum, and are hard to be stabilized in the second gap. The predicted dark gap solitons are observable in current experiments on dense ultracold atoms, using an optical lattice technique, and in the optics domain for nonlinear light propagation in periodic optical media with quintic nonlinearity. ? 2021 American Physical Society.
Accession Number: 20210609889094
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Record 395 of
Title:A new type of unitized design for the structure of a space camera using topology optimization
Author(s):Ye, Jing(1); Song, Yang(2); Duan, Yongqiang(2); Hu, Yongming(2); Hu, Bin(1)
Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 11761 Issue: DOI: 10.1117/12.2586549 Published: 2021
Abstract:Mechanical structure, of which a trade-off between weight and strength has always been considered primely, is important for a space camera as a hub for other assemblies such as optics parts, electronic parts, etc. Traditionally the space camera is composed of a nearly line-up of arrangements containing different units, which is easy to assemble and manufacture, however, not a good type for mechanical properties due to the cantilever structure. We present a new type of unitized design for the structure of the space camera, which unite the tube and the electric cabinet as one unit, with the PCBs (Printed Circuit Boards) surrounded. The main frame is optimized by using topology optimization, improving the characteristic of the structure. The maneuverability has also been considered. Compared with some traditional type, the new type proved to be lighter and more compact, which is beneficial to the mechanical properties and the cost control of satellite launching. ? COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.
Accession Number: 20210509874609
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Record 396 of
Title:Broadband hybrid plasmonic graphene modulator operating at mid-Infrared wavelength
Author(s):Ban, Xiaoqiang(1,2); Zhong, Ming(3); Little, Brent E.(1,2)
Source: Optik Volume: 247 Issue: DOI: 10.1016/j.ijleo.2021.168036 Published: December 2021
Abstract:A broadband modulator with hybrid plasmonic graphene waveguide is proposed. The waveguide is very convenient to transfer graphene and improve fabrication tolerance. We use tip enhancement effect of graphene-based hybrid wedge SPPs mode to enhance light absorption modulation. The interaction between the hybrid plasmonic graphene structure and the optical field is numerically investigated. We get the geometrical optimization value by sweeping the parameter with FDTD method. The result demonstrates that modulation depth of our proposed modulator exceeds 3 dB when wavelength changes from 3.3 to 3.7 μm. Moreover, compared with previous papers, our proposed modulator can obtain broader modulation bandwidth (156.49 GHz) and need lower power consumption (477 fJ/bit), which has a better performance in potential applications such as optoelectronic countermeasure systems and optical signal processing. ? 2021 Elsevier GmbH
Accession Number: 20214010971052
