2020
2020
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Record 409 of
Title:Temperature-dependent analysis of solid-state photon-enhanced thermionic emission solar energy converter
Author(s):Yang, Yang(1,2); Cao, WeiWei(1,3,4); Xu, Peng(1,4); Zhu, Bing Li(1,5); Bai, Yong Lin(1,2); Wang, Bo(1); Qin, Jun Jun(2,5); Bai, Xiao Hong(2)Source: Energies Volume: 13 Issue: 7 DOI: 10.3390/en13071554 Published: 2020Abstract:Solid-state photon-enhanced thermionic emission (PETE) solar energy converters are newly proposed devices that can directly convert solar energy into electrical power at high temperatures. An analytical model based on a one-dimensional steady-state equation is developed to analyze the temperature-dependent performance of the solid-state PETE converter. The treatment used to derive the reverse saturation current density (J0) and open-circuit voltage (Voc) of the solid-state PETE converter is similar to that used in photovoltaic cells. Thus, their performances at elevated temperatures can be compared. Analysis results show that J0 of the solid-state PETE converter with a GaAs absorption layer is approximately three orders of magnitude lower, and the decrease rate of open-circuit voltage (-dVoc/dT) is smaller than that of a practical GaAs photovoltaic cell. The improved performance of the solid-state PETE converter at high temperatures is attributed to the simultaneous use of diffiusion and ballistic transport to harvest photo-generated electrons. The results presented in this paper demonstrate that, besides using wide bandgap materials and increasing doping density, harvesting solar energy via PETE effect can effectively improve the performance of solar cells at elevated temperatures. ? 2020 by the authors.Accession Number: 20201508404498 -
Record 410 of
Title:41.8 W output power, 200 kHz repetition rate ultra-fast laser based on Yb:YAG single crystal fiber(SCF)amplifier
Author(s):Wang, Na Na(1,2); Wang, Xiang Lin(1); Hu, Xiao Hong(1); Zhang, Ting(1); Yuan, Hao(1); Zhang, Wei(1); Li, Feng(1); Wang, Yi Shan(1,2); Zhao, Wei(1,2)Source: Optics and Laser Technology Volume: 127 Issue: DOI: 10.1016/j.optlastec.2020.106202 Published: July 2020Abstract:We demonstrate a high repetition rate, high energy chirped pulse amplification (CPA) system based on single crystal fiber (SCF) amplifier. With home-made all-fiber laser as the seed laser and Yb:YAG rod, SCF as the amplification gain medium, an output power of 61.8 W at 200 kHz repetition rate has been obtained. To the best of our knowledge, this is the highest power based on SCF at hundreds of kHz repetition rate. The measured M2 values are approximately 1.241 in the horizontal and 1.186 in the vertical direction. The spectrum width is 3.8 nm, which support Fourier transform-limited pulse duration of 411 fs. An average power of 41.8 W with pulse duration of 1.5 ps has been obtained after the chirped volume Bragg grating (CVBG) compressor, which will be compressed to hundreds of fs with accurate chirp compensation. ? 2020 Elsevier LtdAccession Number: 20201108290305 -
Record 411 of
Title:Progress and Prospect of Research on Single-molecule Localization Super-resolution Microscopy(Invited Review)
Author(s):An, Sha(1,2); Dan, Dan(1); Yu, Xiang-Hua(1); Peng, Tong(1,2); Yao, Bao-Li(1,2)Source: Guangzi Xuebao/Acta Photonica Sinica Volume: 49 Issue: 9 DOI: 10.3788/gzxb20204909.0918001 Published: September 1, 2020Abstract:Super-resolution optical microscopy breaks through the diffraction limit and becomes a powerful tool for the modern biomedical research with the development of novel fluorescence probes, advanced lasers, high sensitivity photodetectors, etc. Single-molecule Localization Microscopy (SMLM), as one of the super-resolution technologies, can resolve the subcellular structures in nanoscale by using the photoswitching effect of certain fluorescence probes. In this paper, the principle and implementation of SMLM are introduced, the applications in the fields of cytobiology, tissue biology and neuroscience are presented, furthermore, the development trends and the futher investigated directions of this technique are discussed, providing references for the relevant research fields. The continuous innovation of super-resolution microscopy will promote the development of life science. ? 2020, Science Press. All right reserved.Accession Number: 20203909224751 -
Record 412 of
Title:Propagation properties of standard and elegant Herimite-Gaussian beams in oceanic turbulence
Author(s):Wang, Hao(1,2); Kang, Fu-Zeng(1); Zhao, Wei(1); Li, Yi-Chao(1,2)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 11427 Issue: DOI: 10.1117/12.2553066 Published: 2020Abstract:The analytical expressions of the M2-factor for laser beams propagating in oceanic turbulence are derived by using the extended Huygens-Fresnel principle and the definition of the second moment of the Wigner distribution function(WDF). Taking the standard Hermite-Gaussian (SHG) beams and elegant Hermite-Gaussian (EHG) beams as typical examples of laser beams, the propagation properties of the SHG beams and EHG beams in oceanic turbulence are analyzed quantitatively. It is shown that in oceanic turbulence the M2-factor of SHG and EHG beams are different except for beam order m=0 and m=1. At a given propagation distance, the relative M2-factor of SHG and EHG beams in turbulence monotonously decreases with increasing beam order. The relative M2-factor of SHG beams are less than those of EHG beams under the same condition, implying that turbulence influences SHG beams less than EHG beams. ? COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.Accession Number: 20201108282739 -
Record 413 of
Title:Repetition-rate multiplicable soliton microcomb generation and stabilization via phase-modulated pumping scheme
Author(s):Zhao, Bailing(1,2); Wang, Leiran(1,2); Sun, Qibing(1,2); Lu, Zhizhou(1,2); Liu, Mulong(1,2); Wang, Weiqiang(1); Wang, Guoxi(1,2); Gao, Cunxiao(1); Zhang, Wenfu(1,2); Zhao, Wei(1,2)Source: Applied Physics Express Volume: 13 Issue: 3 DOI: 10.35848/1882-0786/ab7481 Published: March 1, 2020Abstract:We numerically demonstrate repetition rate multiplicable soliton microcomb generation using the phase-modulation pump scheme (PMS). Dissipative Kerr solitons are directly obtained avoiding the primary comb and chaotic modulation-instability stage and the repetition rate can be multiplied by changing the modulation frequency with fixed intensity. The PMS can not only help to stabilize emitted solitons with inhibited temporal drift against the Raman self-frequency shift effect, but also achieve soliton spacing equalization recovered from certain position fluctuations. Such approach can enable delicate manipulation on soliton behaviors, and provide a feasible route to soliton microcombs with even higher repetition rates and improved stabilities. ? 2020 The Japan Society of Applied Physics.Accession Number: 20201508385688 -
Record 414 of
Title:OAM Mode Transmission Characterization of Hollow Ring-core POF Related to Geometric Tolerance
Author(s):Yuan, Yuan(1,2); Kong, De-Peng(1); He, Zheng-Quan(1); Wang, Li-Li(1)Source: Guangzi Xuebao/Acta Photonica Sinica Volume: 49 Issue: 6 DOI: 10.3788/gzxb20204906.0606002 Published: June 1, 2020Abstract:The influences of the geometric deformation of the fiber such as ellipse, misalignment and diametrical nonuniformity on the performance of Orbital Angular Momentum (OAM) modes propagated in the Hollow Ring-core Polymer Optical Fiber (HRC-POF) are studied by full vector finite element method. In addition, the maximum deformation that the fiber can withstand under the condition that maintains the stable transmission of the OAM mode is also studied. The results show that the ellipse and misalignment will cause the mode walk-off upon propagation, leading to the decrease of the purity of synthesized OAM modes and the increase of the crosstalk. Numerical results show that the purity of synthesized OAM modes is more than 99.02% and the crosstalk is less than -20.08 dB when the ellipticity or misalignment is within 1.0%. The diametrical nonuniformity of the fiber will only affect the number of OAM modes supported in the HRC-POF. The larger the core radius is, the more OAM modes can be transmitted in the fiber. Besides, the original 26 OAM modes can be supported in HRC-POF when the diametrical nonuniformity is -3% to 10%. ? 2020, Science Press. All right reserved.Accession Number: 20202708899071 -
Record 415 of
Title:Influence of Strain on Performance of Independent Emitters in High Power Quasi-continuous 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)Source: Guangzi Xuebao/Acta Photonica Sinica Volume: 49 Issue: 9 DOI: 10.3788/gzxb20204909.0914001 Published: September 1, 2020Abstract:In order to study the issues of non-uniform performance of the emitters in laser bars, 960 nm laser bars with 38 emitters and cavity length of 2 mm packaged by the microchannel cooler were experimentally studied. The peak output power reaches 665.6 W, the electro-optic conversion efficiency is 63.8%, and the centroid wavelength is 959.5 nm under the driving current of 600 A and the duty ratio of 10%. Firstly, theoretical analysis was made to find out the relationship between the external stress and laser's parameter changes. Then, the laser photoelectric characteristics parameters such as threshold current, slope efficiency, spectrum and optical power were measured via the test setup. From external stress theory, it is clear that external stress can significantly affect the laser's parameter performance. Specifically, compressive strain will cause blue-shift in wavelength, decrease in threshold current, and increase in laser and slope efficiency; tensile strain by contrast, will have completely opposite effects on the laser performance. Studies have shown the performance that affects the internal emitters is not only thermal effects, but also residual strain after packaging. The distribution of stress can basically predict the pattern of array performance, which will provide a reference for the development of high peak power, high reliability semiconductor laser arrays. ? 2020, Science Press. All right reserved.Accession Number: 20203909225456 -
Record 416 of
Title:Mid-infrared dual-comb generation via the cross-phase modulation effect in a normal-dispersion microcavity
Author(s):Guo, Liujun(1,2); Wang, Leiran(1,2); Sun, Qibing(1,2); Liu, Mulong(1,2); Wang, Guoxi(1); Wang, Weiqiang(1); Xie, Peng(1,2); Fan, Weichen(1,2); Zhao, Wei(1,2)Source: Applied Optics Volume: 59 Issue: 7 DOI: 10.1364/AO.385401 Published: March 1, 2020Abstract:We numerically demonstrate orthogonally polarized dual-comb generation in a single microcavity with normal dispersion assisted by the cross-phase modulation (XPM) effect. It is found that the XPM effect facilitates the emission of a secondary polarized comb with different temporal properties in a wide existence range covering the blue- to red-detuned regime and thus releases the requirements for delicate control on the detuned region of pump frequency. Also, the energy transfer between two polarization components together with the normal-dispersion property contributes to a more balanced intensity difference and significantly increased conversion efficiency from the pump light into the comb operation. This work could provide a route to a low-cost and compact mid-infrared dual-comb system with a lower power requirement aswell as an effective approach to higher comb teeth power with improved efficiency for practical applications. ? 2020 Optical Society of America.Accession Number: 20201008269831 -
Record 417 of
Title:Near-infrared Properties of Optical Planar Waveguides Formed by H+ Ion Implantation in Yb3+-doped Phosphate Glasses
Author(s):Lü, Jing-Yan(1); Guo, Hai-Tao(2); Xu, Jun(3); Liu, Chun-Xiao(1)Source: Guangzi Xuebao/Acta Photonica Sinica Volume: 49 Issue: 4 DOI: 10.3788/gzxb20204904.0423001 Published: April 1, 2020Abstract:The Yb3+-doped phosphate glass waveguides by the hydrogen-ion implantation under the condition of energies of (0.5+0.55) MeV and doses of (1.0+2.0) × 1016 ions/cm2 were fabricated, and characteristics of the waveguide were studied in the near-infrared band. The change of refractive index after the implantation was measured by the prism coupling method, which corresponded well with the calculated effective refractive index by the reflectivity calculation method. The formation theory of the ion-implanted planar waveguides was discussed through simulating the vacancy distribution induced by the irradiation. The propagation mode of light in the waveguide was simulated by using the FD-BPM, which suggested that the near-infrared waveguide structure could be fabricated by irradiating the Yb3+-doped phosphate glass with the energetic hydrogen ions. ? 2020, Science Press. All right reserved.Accession Number: 20202008654231 -
Record 418 of
Title:Graphene oxide functionalized micro-tapered long-period fiber grating for sensitive heavy metal sensing
Author(s):Wang, Ruiduo(1,2); Ren, Zhaoyu(3); Kong, Depeng(1); Wu, Hao(3); Hu, Baowen(1); He, Zhengquan(1)Source: Applied Physics Express Volume: 13 Issue: 6 DOI: 10.35848/1882-0786/ab8b53 Published: June 1, 2020Abstract:We report a Ni2+ heavy metal sensor based on a graphene oxide (GO) functionalized micro-tapered long-period fiber grating (MTLPG) where light-matter interaction is enhanced. With high-quality GO coating on fiber with strong adhesion and controllable thickness, the GO-coated MTLPG demonstrated a resonant wavelength shift and intensity change, corresponding to a sensitivity of up to 5.12 10-4 nm ppb-1 and 3.07 10-4 dB ppb-1, respectively. Moreover, the limits of detection were 2.5 ppb and 0.27 ppb, respectively, operating in a wider concentration range of 1 ppb to 1 107 ppb. The proposed optical platform can be developed for superior chemical sensing applications. ? 2020 The Japan Society of Applied Physics.Accession Number: 20202308779892 -
Record 419 of
Title:One-dimensional localized modes of spin-orbit-coupled Bose-Einstein condensates with spatially periodic modulated atom-atom interactions: Nonlinear lattices
Author(s):Chen, Junbo(1,2); Zeng, Jianhua(1,2)Source: Communications in Nonlinear Science and Numerical Simulation Volume: 85 Issue: DOI: 10.1016/j.cnsns.2020.105217 Published: June 2020Abstract:Bose-Einstein condensates (BECs) provide a clear and controllable platform to study diverse intriguing emergent nonlinear effects that appear too in other physical settings, such as bright and dark solitons in mean-field theory as well as many-body physics. Various ways have been elaborated to stabilize bright solitons in BECs, three promising schemes among which are: optical lattices formed by counterpropagating laser beams, nonlinear managements mediated by Feshbach resonance, spin-orbit coupling engineered by dressing atomic spin states (hyperfine states of spinor atomic BECs) with laser beams. By combing the latter two schemes, we discover, from theory to calculations, that the two-component BECs with a spin-orbit coupling and cubic atom-atom interactions, whose nonlinear distributions exhibit a well-defined spatially periodic modulation (nonlinear lattice), can support one-dimensional localized modes of two kinds: fundamental solitons (with a single peak), and soliton pairs comprised of dipole solitons (anti-phase) or two-peak solitons (in-phase). The influence of three physical parameters: chemical potential of the system, strengths of both the Rashba spin-orbit coupling and atom-atom interactions, on the existence and stability of the localized modes is investigated based on linear-stability analysis and direct perturbed simulations. In particular, we demonstrate that the localized modes can be stable objects provided always that both the inter- and intraspecies interactions are attractive. ? 2020 Elsevier B.V.Accession Number: 20200708168534 -
Record 420 of
Title:Depth-micro Laser Drilling Methods Based on Spatial Light Modulator
Author(s):Song, Chang(1,2); Yang, Xiao-Jun(1); Zhao, Wei(1); Duan, Yu-Fei(1,2)Source: Guangzi Xuebao/Acta Photonica Sinica Volume: 49 Issue: 8 DOI: 10.3788/gzxb20204908.0814001 Published: August 1, 2020Abstract:In the galvo scanning laser drilling systems, the depth of processing is usually limited due to the short focal length. To solve this problem, a method based on high damage threshold spatial light modulator loading Fresnel lens phase is proposed. The focal length of the Fresnel lens is adjusted to change the position of the focus. As the machining depth increases, the focus position moves downward. Then the experiment processing and testing were carried out. The experimental results show that a high quality microhole with a diameter of about 330 microns was machined on stainless steel sample by using the method. The new method uses galvo scanning laser drilling systems and spatial light modulator to process microhole, which has a good application prospect in the field of laser processing. ? 2020, Science Press. All right reserved.Accession Number: 20203709159332