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2020

• Record 397 of
  
  Title:Applications of Holographic Optical Tweezers in Biological Research
  
  Author(s):Liang, Yansheng(1); Yao, Baoli(2); Lei, Ming(1)
  Source: Zhongguo Jiguang/Chinese Journal of Lasers  Volume: 47  Issue: 2  DOI: 10.3788/CJL202047.0207020  Published: February 10, 2020  
  Abstract:As noninvasive tools of high-resolution micromanipulation and force measurement, optical tweezers have been widely applied to researches in life science. Holographic optical tweezers show higher flexibility than the conventional single-trap optical tweezers in producing arbitrarily patterned trap arrays with the help of the spatial light modulator, which has significant potential in application to the biomedical research. In this paper, we review the basic principle of holographic optical tweezers, hologram algorithm, and the progress in the applications of holographic optical tweezers in biological research. We expect that this review will provide a helpful reference to the community that will apply holographic optical tweezers to the biological research. ? 2020, Chinese Lasers Press. All right reserved.
  Accession Number: 20201208333706
• Record 398 of
  
  Title:A high-performance annularly stacked laser diode pump for a solid state laser
  
  Author(s):Li, Junli(1); Sun, Lichen(1); Liu, Ming(1); Han, Yang(1); Fu, Tuanwei(1); Cai, Lei(1); Zheng, Yanfang(1); Yan, Minna(1); Wang, Juan(1); Tao, Chunhua(1); Gao, Lijun(1); Wang, Jingwei(1); Zah, Chungen(1); Liu, Xingsheng(1,2)
  Source: Proceedings of SPIE - The International Society for Optical Engineering  Volume: 11545  Issue:   DOI: 10.1117/12.2573534  Published: 2020  
  Abstract:A high peak power annularly-stacked laser diode pump has been designed and manufactured for a solid state laser (SSL), which is constructed by 12 single annular stacks composed of 3-bar laser diode (LD) submodules. High peak power and high wavelength uniformity have been considered. Macro channel cooling has been used during the operation of the annular stacks, at typical coolant flow rate of 2L/min. Heat dissipation and stress of a single annular stack have been simulated by finite element software, which shows high temperature uniformity of 3-bar submodules (± 0.5°C) and low package stress (11.8MP). The peak power of the annularly stacked laser diode pump has reached 234kW at a peak current of 450A or less. A high uniformity of centroid wavelength (802 ±lmn) with a full width at half maximum (FWHM) of 4nm has been measured. More than 24 million shots have been verified for the 3-bar LD submodules. ? 2020 SPIE.
  Accession Number: 20204809536194
• Record 399 of
  
  Title:Numerical investigation of the periodical complementary dielectric-barrier discharge equipped with double-ring electrodes in atmospheric helium
  
  Author(s):Wang, Jing(1,2); Li, Jing(1,2); Lei, Bingying(1,2); Xing, Yufei(1,2); Xu, Boping(1,2); Liu, Yinghua(1,2); Li, Xinzhong(1,2); Wang, Yishan(1,2); Tang, Jie(1,2); Zhao, Wei(1,2); Duan, Yixiang(1,2)
  Source: Physics of Plasmas  Volume: 27  Issue: 7  DOI: 10.1063/5.0009695  Published: July 1, 2020  
  Abstract:A two-dimensional fluid model was used to investigate the characteristics of helium dielectric-barrier discharge (DBD) equipped with double-ring electrodes at atmospheric pressure. Simulation results show that although the temporal evolutions of discharge current and current density at different radial positions exhibit the same or similar characteristics to those in traditional DBD, a distinctive spatial discharge structure is observed during the discharge process. The spatial distribution of electron density at current peak moments exhibits a periodical complementary feature between the center-advantage and the periphery-advantage with the inner ring electrode covering the radial axis from 0.5 to 1.0 mm. When the inner ring electrode covers the radial axis from 1.0 to 1.5 mm, the spatial distribution of electron density satisfies another periodical complementary behavior between the electrode-center-advantage and the coexistence of periphery-advantage and center-advantage. These complementary discharge features mainly result from non-uniform electric field and surface charge distribution at the end of the previous discharge. The difference of the discharge structure between the two cases is attributed to the fact that Laplacian field distributions are largely dependent on the arrangement of double-ring electrodes. Our observations show that electrode geometry plays an important role in the formation of the discharge structure. ? 2020 Author(s).
  Accession Number: 20203409078798
• Record 400 of
  
  Title:Molybdenum Disulfide Film Saturable Absorber Based on Sol-Gel Glass and Spin-Coating Used in High-Power Q-Switched Nd:YAG Laser
  
  Author(s):Wang, Jiang(1); Chen, Zhendong(1); Wang, Yonggang(1); Wang, Taijin(1); Liu, Sicong(1); Chen, Guanghua(2); Wang, Yishan(3); Ren, Wei(4); Li, Lu(4)
  Source: ACS Applied Materials and Interfaces  Volume: 12  Issue: 8  DOI: 10.1021/acsami.9b14494  Published: February 26, 2020  
  Abstract:In recent years, many different kinds of nonlinear optical materials have been applied to passively Q-switched solid-state lasers. However, the average output powers of these lasers are typically limited to 1 W due to the low damage threshold of the materials. In this study, a molybdenum-disulfide-doped glass-composite absorber was synthesized using the sol-gel method and spin-coating technique. The optical damage threshold of the absorber reached 3.17 J/cm2. Saturation intensity, modulation depth, and nonsaturable loss are 9.35 MW/cm2, 8.41%, and 9.14%, respectively. After inserting the absorber into a linear Nd:YAG laser cavity, the maximum average output power (3.22 W) and stable Q-switched laser pulses duration (132 ns) were obtained. Copyright ? 2020 American Chemical Society.
  Accession Number: 20201108276208
• Record 401 of
  
  Title:Theoretical and experimental investigation of secondary electron emission characteristics of MgO coating produced by atomic layer deposition
  
  Author(s):Guo, Junjiang(1,2,3); Wang, Dan(5); Wen, Kaile(3,6); Xu, Yantao(1,3); Zhu, Xiangping(1,3); Liu, Lutao(1,3); Cao, Weiwei(1,3); Si, Jinhai(2); Lu, Min(1); Guo, Haitao(1,4)
  Source: Ceramics International  Volume: 46  Issue: 6  DOI: 10.1016/j.ceramint.2019.12.067  Published: 15 April 2020  
  Abstract:Atomic layer deposition (ALD) is utilized to prepare thin MgO coatings 1–50 nm on Si substrate. In addition, secondary electron emission (SEE) coefficient of MgO/Si double-layered structure is evaluated as a function of coating thickness and primary electron (PE) energy. After neutralizing the surface of test specimen, we have accurately analyzed the relationship between secondary electron yield (SEY) of MgO coating and PE energy. Meanwhile, SEE characteristics of MgO/Si double-layered structure have been systematically analyzed. A maximum SEY value of 6.15 has been achieved at coating thickness of 30 nm and PE energy of 550 eV. Furthermore, theoretical model is established by using Dionne's SEE model to analyze experimentally measured SEY data, demonstrating consistency between experimentally measured and theoretically calculated results. This work demonstrates that SEE level of MgO coating can be optimized by tuning coating thickness and presents novel insights into SEE characteristics of composite materials. Those results can serve as a baseline for further design and fabrication of a wide array of electronic devices. ? 2019 Elsevier Ltd and Techna Group S.r.l.
  Accession Number: 20195007829219
• Record 402 of
  
  Title:A 51.3 W, sub-kHz-linewidth linearly polarized all-fiber laser at 1560 nm
  
  Author(s):Xue, Mingyuan(1,2); Gao, Cunxiao(1); Niu, Linquan(1); Zhu, Shaolan(1); Sun, Chuandong(1)
  Source: Laser Physics  Volume: 30  Issue: 3  DOI: 10.1088/1555-6611/ab67ce  Published: 2020  
  Abstract:We demonstrate a continuous-wave high output power and narrow linewidth all-fiber master oscillator power amplifier laser at 1560 nm. The laser output power is 51.3 W with 36.38% optical-to-optical conversion efficiency and a linewidth of 0.865 kHz. The measured signal-to-noise ratio is 49 dB, and the polarization extinction ratio is greater than 20 dB. The laser can be used for high-efficiency nonlinear frequency conversion. ? 2020 Astro Ltd.
  Accession Number: 20201408365398
• Record 403 of
  
  Title:Preparation and Mid-infrared Luminescence Properties of Transition Metal Co2+ Doped ZnS Sulfide Nanocrystals
  
  Author(s):Wen, Chang-Xiu(1,2); Shi, Hua-Wei(1,2); Chen, Mei-Ling(1,2); Xiao, Xu-Sheng(1); Guo, Hai-Tao(1); Cui, Xiao-Xia(1)
  Source: Guangzi Xuebao/Acta Photonica Sinica  Volume: 49  Issue: 2  DOI: 10.3788/gzxb20204902.0216001  Published: February 1, 2020  
  Abstract:Co2+:ZnS sulfide nanocrystals are prepared by a simplified hydrothermal method without organic materials. These nanocrystals have a cubic sphalerite structure with an average grain size of around 8. 3 nm. Mid-infrared fluorescence emissions at 3 400 nm and 4 700 nm were detected under 808 nm laser pumping. By heat treatment at 800℃ in a reducing atmosphere, the prepared nanocrystals transfered to cubic sphalerite and wurtzite mixed crystal forms, and the average grain size increaes to 22.5 nm. After the heat treatment, the nanocrystals possess lower hydroxyl content on surface, therefore exhibit stronger mid-infrared fluorescence. This method is facile and aviods the introduction of organic mid-infrared fluorescence quenching centers during the preparation of Co2+:ZnS nanocrystals. The surface defects and hydroxy content of Co2+:ZnS nanocrystals were reduced and more stronger mid-infrared fluorescence was obtained after heat treatment. ? 2020, Science Press. All right reserved.
  Accession Number: 20201308337493
• Record 404 of
  
  Title:Antenna Array Initial Condition Calibration Method for Integrated Optical Phased Array
  
  Author(s):Zhang, Qi-Hao(1,2); Zhang, Ling-Xuan(1); Li, Zhong-Yu(1); Wu, Wei(1,2); Wang, Guo-Xi(1,2); Sun, Xiao-Chen(1,2); Zhao, Wei(1,2); Zhang, Wen-Fu(1,2)
  Source: Guangzi Xuebao/Acta Photonica Sinica  Volume: 49  Issue: 7  DOI: 10.3788/gzxb20204907.0726001  Published: July 1, 2020  
  Abstract:To solve the problem that the phase error of the optical phased array is difficult to calibrate, rotating element electric field vector calibration method is modified. Comparing with the traditional method, the new method modifies the algorithm and corrects the phase immediately after measuring the phase error of one unit, then measures and corrects the phase of the next unit. Possible π phase error in traditional method is avoided when large initial phase distribution and finite optical power measurement accuracy present. The simulation results show that the main lobe intensity calibrated with the original method reaches at most 70.8% of the ideal value on average, and the standard deviation is at least 19.1%. While after calibration with the modified method the main lobe intensity reaches at least 87.6% of the ideal value on average, the maximum standard deviation is 7.3%. The modified method produces statistically more accurate and predictable calibration result. A 9×9 optical phased array chip is manufactured. The initial grating lobe suppression ratio ofthe chip is 2.12 dB. Calibrated with this modified method the ratio reaches 4.68 dB. The effectiveness and practical application value of this method are proved. ? 2020, Science Press. All right reserved.
  Accession Number: 20203309050381
• Record 405 of
  
  Title:All-optical logic gates based on fwm in a symmetric hybrid plasmonic silicon waveguide
  
  Author(s):Wu, Wei(1,2); Sun, Qibing(1,2); Zhao, Wei(1,2)
  Source: Optics InfoBase Conference Papers  Volume:   Issue:   DOI: 10.1364/FIO.2020.JTu1B.8  Published: September 14, 2020  
  Abstract:We propose a symmetric hybrid plasmonic silicon waveguide (SHPWG), which could offer broadband flattened dispersion and high nonlinearity. All-optical logic XOR gates for 100 Gb/s signals is realized via four-wave mixing (FWM) in the C-band. ? OSA 2020 ? 2020 The Author(s)
  Accession Number: 20212110391426
• Record 406 of
  
  Title:Hybrid CPA system comprised by fiber-silicate glass fiber-single crystal fiber with femtosecond laser power more than 90 W at 1 MHz
  
  Author(s):Li, Feng(1); Yang, Zhi(1); Lv, Zhiguo(1); Duan, Yufei(1,2); Wang, Nana(1,2); Yang, Yang(1); Li, Qianglong(1); Yang, Xiaojun(1); Wang, Yishan(1); Zhao, Wei(1)
  Source: Optics and Laser Technology  Volume: 129  Issue:   DOI: 10.1016/j.optlastec.2020.106291  Published: September 2020  
  Abstract:A high power and hybrid chirped pulse amplification (CPA) system comprised by fiber-silicate glass fiber-single crystal fiber amplifier is demonstrated in this work. In this hybrid system, the high gain compact silicate glass fiber amplifier is used to boost the power, amplified power more than 92 W is obtained with the injected power of 400 mW at 1 MHz, corresponded amplification gain as high as 23.6 dB. To our best knowledge, this is the highest power obtained in CPA amplification with silicate glass fiber. The single crystal fiber amplifier is used to boost the energy with low nonlinearity in high pulse energy amplification. Amplified power of 122 W at 1 MHz is obtained, corresponding to a pulse energy of 122 μJ. After amplification, the laser pulses are compressed by chirped volume Bragg grating (CVBG), the total compression efficiency greater than 73% is obtained by control the spectrum width with a fiber filter with pass band of 5 nm in the fiber pre-amplifier to match the reflected bandwidth of the CVBG compressor. To match the dispersion between the chirped fiber Bragg grating (CFBG) stretcher and the CVBG compressor, the self-made temperature tuning device of CFBG is employed to make precision dispersion match. The optimized pulse width of 660 fs at compressed power of 90 W is obtained. This compact and high power ultrafast laser will find various applications in scientific research and industrial applications. ? 2020 Elsevier Ltd
  Accession Number: 20201808587457
• Record 407 of
  
  Title:Analysis on High Temperature Characteristic of High Power Semiconductor Laser Array
  
  Author(s):Li, Bo(1,2); Wang, Zhen-Fu(1); Qiu, Bo-Cang(1); Yang, Guo-Wen(1,2); Li, Te(1); Zhao, Yu-Liang(1,2); Liu, Yu-Xian(1,2); Wang, Gang(1,2); Bai, Shao-Bo(1); Du, Yu-Qi(1,2)
  Source: Faguang Xuebao/Chinese Journal of Luminescence  Volume: 41  Issue: 9  DOI: 10.37188/fgxb20204109.1158  Published: September 1, 2020  
  Abstract:The demand for high peak power semiconductor laser arrays in high temperature working conditions is becoming more and more prominent. The high peak power 960 nm semiconductor laser arrays packaged by microchannel cooler were experimentally studied through the precision temperature control system. A series of output characteristics such as the peak power, power conversion efficiency, working voltage and spectrum are tested from 10℃ to 80℃, combined with theoretical analysis. The energy loss distribution of power conversion efficiency is given at different temperatures. The results show that the power conversion efficiency drops from 63.95% to 47.68% after the operating temperature increases from 10℃ to 80℃, and the proportion of carrier leakage losses increases from 1.93% to 14.85%, which is the main factor that causes the decline in the power conversion efficiency. This study has important guiding significance for high peak power semiconductor laser arrays in high temperature applications and laser chip design. ? 2020, Science Press. All right reserved.
  Accession Number: 20204109330531
• Record 408 of
  
  Title:Theoretical and experimental investigation of secondary electron emission characteristics of ALD-ZnO conductive films
  
  Author(s):Zhu, Xiangping(1,2); Guo, Junjiang(1,2,3,4); Cao, Weiwei(1,2,3,4,5); Liu, Lutao(1,2); Zhang, Guangwei(6); Sun, Xin(3); Zhao, Wei(1,2); Si, Jinhai(4)
  Source: Journal of Applied Physics  Volume: 128  Issue: 6  DOI: 10.1063/5.0014590  Published: August 14, 2020  
  Abstract:Microchannel plates (MCPs) are widely utilized as key device components in various photomultipliers; however, the performance of MCPs cannot be further improved by traditional processing. Atomic layer deposition (ALD) is a promising route to prepare a composite conductive layer and secondary electron emission (SEE) layer structure on the inner wall of the MCP. Moreover, ZnO is an essential component of a composite conductive layer, which is located at the bottom of the SEE layer and significantly influences the SEE coefficient, which, in turn, affects the gain performance of MCPs. Herein, ALD is used to deposit different thicknesses of ZnO films (1-50 nm) on an Si substrate, resulting in an ZnO/Si double-layer film structure. The relationship between the SEE coefficient and the primary electron energy of ZnO films with different thicknesses was established. The maximum secondary electron yield value of 2.04 is achieved at a film thickness of 30 nm. Moreover, Dionne's SEE model and theory of semiconductors are used to simulate and verify the experimental results. These results provide useful guidelines for the development of ALD-MCPs. ? 2020 Author(s).
  Accession Number: 20203609136407