2022

• Record 157 of
  
  Title:Stokes Localized Structure in Kerr Resonators
  
  Author(s):Liu, Mulong(1); Huang, Huimin(2); Lu, Zhizhou(3); Dang, Yaai(1); Mei, Sen(1); Wang, Chang(1); Zhao, Bailing(3); Zhao, Wei(4)
  Source: Physical Review Applied  Volume: 18  Issue: 4  DOI: 10.1103/PhysRevApplied.18.044028  Published: October 2022  
  Abstract:We theoretically demonstrate generation of the Stokes temporal localized structure (TLS) by exploiting its Raman interaction in space and time within an optical potential well shared with another dark pulse. Excitation of the Stokes TLSs is feasible in both the normal and anomalous group-velocity dispersion regime, with a single modulated pump source. Stimulated Raman scattering constitutes influences on the stability and physical feature of the generated Stokes TLS (STLS). Particularly, breathing STLSs are also observed due to the periodic energy transfer between the primary and the Stokes fields. These findings could deepen the understanding of complex nonlinear dynamics in resonators and facilitate the excitation of different types of TLSs in potential platforms. © 2022 American Physical Society.
  Accession Number: 20224513055520
• Record 158 of
  
  Title:Epitaxially-Stacked High Efficiency Laser Diodes Near 905 nm
  
  Author(s):Zhao, Yuliang(1,2); Yang, Guowen(1,2); Zhao, Yongming(3); Tang, Song(3); Lan, Yu(1,2); Liu, Yuxian(1,2); Wang, Zhenfu(1); Demir, Abdullah(4)
  Source: IEEE Photonics Journal  Volume: 14  Issue: 6  DOI: 10.1109/JPHOT.2022.3211964  Published: December 1, 2022  
  Abstract:We report on studying tunnel junctions and an optical cavity structure for developing epitaxially-stacked high-efficiency 905 nm high-power laser diodes. The GaAs tunnel junctions were explored via simulations and experiments to realize a high peak current density of 7.7 × 104 A/cm2 and a low specific resistance of 1.5 × 10-5 Ωcm2 with a high n-doping concentration of 6 × 1019 cm-3. Employing a low-loss epitaxial structure design, single-, double-, and triple-cavity structure laser diodes demonstrated power scaling by epitaxial stacking. Triple-cavity laser diodes have a low optical loss (0.42 cm-1) and generate a peak power of 83 W with a short cavity length of 750 μm at a limited current of 30 A. © 2009-2012 IEEE.
  Accession Number: 20224212973253
• Record 159 of
  
  Title:Elimination of catastrophic optical mirror damage in continuous-wave high-power laser diodes using multi-section waveguides
  
  Author(s):Liu, Yuxian(1,2); Ebadi, Kaveh(3); Sunnetcioglu, Ali Kaan(3); Gundogdu, Sinan(3); Sengul, Serdar(3); Zhao, Yuliang(1,2); Lan, Yu(1,2); Zhao, Yongming(4); Yang, Guowen(1,2,4); Demir, Abdullah(3)
  Source: Optics Express  Volume: 30  Issue: 18  DOI: 10.1364/OE.461866  Published: August 29, 2022  
  Abstract:One of the persistent obstacles for high-power laser diodes (LDs) has been the catastrophic optical mirror damage (COMD), which limits the operating power level and lifetime of commercial high-power LDs. The output facet of LD reaches a critical temperature resulting in COMD, which is an irreversible device failure. Here, we fabricate multi-section LDs by tailoring the waveguide structure along the cavity that separates the output facet from the heat-generating lasing region. In this method, the LD waveguide is divided into electrically isolated laser and window sections along the cavity. The laser section is pumped at a high current to achieve high output power, and the window is biased at a low current with negligible heat generation. This design restricts the thermal impact of the laser section on the facet, and the window section allows lossless transport of the laser to the output facet. The lasers were operated continuous-wave up to the maximum achievable power. While standard LDs show COMD failures, the multi-section waveguide LDs are COMD-free. Our technique and results provide a pathway for high-reliability LDs, which would find diverse applications in semiconductor lasers. © 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement.
  Accession Number: 20223412609225
• Record 160 of
  
  Title:A novel microstructured polymer tube for THz vortex beams guidance
  
  Author(s):Yuan, Yuan(1,2); Kong, Depeng(1); Guan, Lei(1); Wang, Lili(1)
  Source: Optics Communications  Volume: 505  Issue:   DOI: 10.1016/j.optcom.2021.127502  Published: February 15, 2022  
  Abstract:A novel microstructured polymer tube (MPT) incorporating a central hollow, ring core, porous outer cladding is proposed for terahertz (THz) orbital angular momentum (OAM) guidance, focusing on the enhancement of the quantity of modes and bandwidth. The proposed MPT can support 70 modes (66 THz OAM ones) with large mode effective refractive index separation (>2.197×10−3) over 0.6∼1.25 THz while maintaining single-mode condition radially, and the number of guiding modes can be further increased by properly equiproportional enhancing the size of the tube. Besides, the designed MPT has strong confinement property, high purity (>97.06%), and flat dispersion over the whole operating bandwidth. The result of this work reveals that this kind of MPT is promising to accelerate the development of the compact, light-weight THz communication system, and can be applied in OAM-based mode-division multiplexing combined with wavelength-division multiplexing technique without multiple-input multiple-output digital signal processing. © 2021 Elsevier B.V.
  Accession Number: 20214211041610
• Record 161 of
  
  Title:High-resolution time-resolved spectroscopy based on hybrid asynchronous optical sampling
  
  Author(s):Hu, Hao(1,2); Yang, Ningning(1,2); Liao, Zichun(1,2); Chen, Liao(1,2); Zhang, Chi(1,2); Wang, Weiqiang(3,4); Zhang, Wenfu(3,4); Zhang, Xinliang(1,2)
  Source: APL Photonics  Volume: 7  Issue: 10  DOI: 10.1063/5.0108680  Published: October 1, 2022  
  Abstract:The capability of characterizing arbitrary and non-repetitive emission spectra with a high resolution in real-time is of great merit in various research fields. Optical frequency combs provide precise and stable frequency grids for the measurement of a single spectral line with high accuracy. Particularly, dual-comb spectroscopy enables spectral measurement with a large bandwidth spanning tens of nanometers, but it is limited to measuring absorption spectra and has to trade-off spectral resolution vs the acquisition frame rate set by the repetition rate. Here, to alleviate these restrictions, we propose and demonstrate time-resolved spectroscopy for an emission spectrum based on hybrid asynchronous optical sampling, which features a spectral resolution of 0.63 pm, a frame rate of 1 MHz, and a measurement bandwidth of 13.6 nm, simultaneously. A mode-locked fiber comb with a repetition frequency of f1 is harnessed to interrogate emission spectral features with high resolution via optical Fourier transform achieved using a time-lens. Subsequently, a soliton microcomb of repetition frequency f2s ≈ 1000f1 serving as a probe pulse implements hybrid asynchronous optical sampling, thus significantly increasing the acquisition rate by nearly 3 orders of magnitude. As a proof-of-concept demonstration, the frequency trajectory of a rapidly scanning laser with a linear chirp of 6.2 THz/s is tracked. We believe that chip-scale microcombs will make the fast and high-resolution emission spectroscopy presented here a powerful tool for widespread applications. © 2022 Author(s).
  Accession Number: 20224613102482
• Record 162 of
  
  Title:Terabit FSO communication based on a soliton microcomb
  
  Author(s):Shao, Wen(1,2,3); Wang, Yang(1,2,3); Jia, Shuaiwei(1,2,3); Xie, Zhuang(1,2,3); Gao, Duorui(1,2,3); Wang, Wei(1,3); Zhang, Dongquan(1); Liao, Peixuan(1,3); LITTLE, Brent E.(1,3); Chu, SAI T.(4); Zhao, Wei(2,3); Zhang, Wenfu(1,3); Wang, Weiqiang(1,3); Xie, Xiaoping(1,2,3)
  Source: Photonics Research  Volume: 10  Issue: 12  DOI: 10.1364/PRJ.473559  Published: December 1, 2022  
  Abstract:Free-space optical (FSO) communication technology is a promising approach to establish a secure wireless link, which has the advantages of excellent directionality, large bandwidth, multiple services, low mass and less power requirements, and easy and fast deployments. Increasing the communication capacity is the perennial goal in both scientific and engineer communities. In this paper, we experimentally demonstrate a Tbit/s parallel FSO communication system using a soliton microcomb as a multiple wavelength laser source. Two communication terminals are installed in two buildings with a straight-line distance of ∼1 km. 102 comb lines are modulated by 10 Gbit/s differential phase-shift keying signals and demodulated using a delay-line interferometer. When the transmitted optical power is amplified to 19.8 dBm, 42 optical channels have optical signal-to-noise ratios higher than 27 dB and bit error rates less than 1 × 10-9. Our experiment shows the feasibility of a wavelength-division multiplexing FSO communication system which suits the ultra-high-speed wireless transmission application scenarios in future satellite-based communications, disaster recovery, defense, last mile problems in networks and remote sensing, and so on. © 2022 Chinese Laser Press.
  Accession Number: 20225113283921
• Record 163 of
  
  Title:High Fidelity MZI-BCG Sensor With Homodyne Demodulation for Unobtrusive HR and BP Monitoring
  
  Author(s):Yang, Fangang(1); Xu, Wei(2,6); Lyu, Weimin(3); Tan, Fengze(4); Yu, Changyuan(3); Dong, Bo(5)
  Source: IEEE Sensors Journal  Volume: 22  Issue: 8  DOI: 10.1109/JSEN.2022.3158070  Published: April 15, 2022  
  Abstract:An all-optical active homodyne detection aided fiber-optic Mach-Zehnder interferometer (MZI) vital signs monitoring system is proposed and investigated. The active homodyne detection is mainly realized by employing a wavelength-tunable vertical-cavity surface-emitting laser (VCSEL) and automatic closed-loop control system (CLCS). It can effectively maintain the MZI sensor to operate around the quadrature point and successfully eliminate the fading effect of output signal induced by low frequency drift. Therefore, high fidelity and high stableness of the ballistocardiograph (BCG) signal is guaranteed. The results show that according to the Bland-Altman and the confidence ellipse analysis, the heart rate (HR) monitoring performance reveals high accuracy and good consistence. What' more, a multiple linear regression-based blood pressure (BP) estimation model is presented, which shows that the BP is highly correlated with I-J-K complex oriented features, including IJ interval, JK interval and JK amplitude. It indeed offers a potential approach to achieve cuff-less BP estimation merely based on the high-fidelity BCG signal. In conclusion, the proposed MZI-BCG monitoring system is simple to use, and it shows great potential in future unobtrusive cardiac monitoring both in home and hospital. © 2001-2012 IEEE.
  Accession Number: 20221111799269
• Record 164 of
  
  Title:Reconstruction of attosecond beating by interference of two-photon transitions on the lithium atom with Rabi oscillations
  
  Author(s):Liao, Yijie(1); Zhou, Yueming(1); Pi, Liang-Wen(2,3); Liang, Jintai(1); Ke, Qinghua(1); Zhao, Yong(1); Li, Min(1); Lu, Peixiang(1,4)
  Source: Physical Review A  Volume: 105  Issue: 6  DOI: 10.1103/PhysRevA.105.063110  Published: June 2022  
  Abstract:We present numerical simulations of the reconstruction of attosecond beating by interference of two-photon transitions (RABBITT) on lithium by solving the three-dimensional time-dependent Schrödinger equation. In our scheme, the infrared (IR) field couples the 2s and 2p states of lithium and leads to the Rabi oscillations of populations between these two states. We analyzed the RABBITT phases of the two peaks in the Rabi-oscillation-induced Autler-Townes splittings. Our results show that the relative phase between these two peaks changes with the photoelectron energy and depends on the intensity of the IR field. Moreover, in the angle-resolved RABBITT measurement, the phases of the two peaks depend differently on the emission angle of photoelectrons. These behaviors are traced back to the different initial phases of the electron wave packets emitted from the dressed 2p states and the competition among different ionization channels. © 2022 American Physical Society.
  Accession Number: 20222712324583
• Record 165 of
  
  Title:Study on adhesive curing process and bonding property of XM-31 silicone rubber
  
  Author(s):Zheng, Xiangke(1); Wang, Peng(1); Kang, Shifa(1); Duan, Zhanjun(1); Jia, Xin(1); Shu, Linsen(2)
  Source: Proceedings of SPIE - The International Society for Optical Engineering  Volume: 12166  Issue:   DOI: 10.1117/12.2606857  Published: 2022  
  Abstract:In order to obtain the microstress bonding curing process and its properties of precision optical components, various curing process schemes of XM-31 adhesive were designed and tested. Firstly, a mirror group simulation structure and hardness testing tool were developed to study the effect of the amount of six vulcanizing agents on the solidification rate of XM-31 adhesive. Secondly, the XM-31 adhesive with the best amount of curing agent was solidified under different temperature conditions.Densitometer, stretch machine, hardness tester and microscope were used to test the material properties of XM-31 adhesive after curing, so as to obtain the bonding performance of XM-31 adhesive under different solidification temperature conditions.Finally, the optimized process is applied to the bonding of optical elements in a star-sensitive lens. The results show that the optimum ratio of matrix adhesive and vulcanizing agent of XM-31 adhesive is 100:3 ∼ 100:4. The volume shrinkage rate of XM-31 adhesive under four curing temperatures were 1.82%, 1.75%, 1.63% and 1.43%, respectively. The curing temperature will significantly improve the adhesive process efficiency, but the adhesive strength and hardness will be reduced. The surface shape index PV and RMS value of a certain type of star sensitive lens can meet the design requirements, when using the preferred process of XM-31 adhesive assembly. © COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.
  Accession Number: 20220911735024
• Record 166 of
  
  Title:Nonlinear localized modes in one-dimensional nanoscale dark-state optical lattices
  
  Author(s):Chen, Zhiming(1,2,3); Zeng, Jianhua(1,4)
  Source: Nanophotonics  Volume: 11  Issue: 15  DOI: 10.1515/nanoph-2022-0213  Published: August 1, 2022  
  Abstract:Optical lattices (OLs) with conventional spatial periodic λ/2, formed by interfering the counterpropagating laser beams with wavelength λ, are versatile tools to study the dynamical and static properties of ultracold atoms. OLs with subwavelength spatial structure have been realized in recent quantum-gas experiment, offering new possibility for nonlinear and quantum control of ultracold atoms at the nano scale. Herein, we study theoretically and numerically the formation, property, and dynamics of matter-wave localized gap modes of Bose-Einstein condensates loaded in a one-dimensional nanoscale dark-state OL consisted of an array of optical subwavelength barriers. The nonlinear localized modes, in the forms of on- and off-site fundamental gap solitons, and dipole ones, are demonstrated; and we uncover that, counterintuitively, these modes exhibit always a cusplike (side peaks) mode even for a deeply subwavelength adiabatic lattice, contrary to the previously reported results in conventional deep OLs where the localized gap modes are highly confined in a single lattice cell. The (in)stability features of all the predicted localized modes are verified through the linear-stability analysis and direct perturbed simulations. Our predicted results are attainable in current ultracold atoms experiments with the cutting-edge technique, pushing the nonlinear control of ultracold atoms with short-period OLs as an enabling technology into subwavelength structures. © 2022 the author(s), published by De Gruyter, Berlin/Boston.
  Accession Number: 20222612296475
• Record 167 of
  
  Title:Sum-frequency generation of 133 mJ, 270 ps laser pulses at 266 nm in LBO crystals
  
  Author(s):Wang, Nan(1,2,3,4); Zhang, Jingyuan(2,3); Yu, Haijuan(2,3); Lin, Xuechun(2,3); Yang, Guowen(1)
  Source: Optics Express  Volume: 30  Issue: 4  DOI: 10.1364/OE.451262  Published: February 14, 2022  
  Abstract:We demonstrate the generation of high-energy (133 mJ) and sub-nanosecond (∼270 ps) deep ultraviolet (DUV) pulses at 266 nm by sum-frequency mixing in LiB3O5 (LBO) crystals. The highest 133 mJ pulse energy ever reported corresponds to a peak power of 0.49 GW and an energy conversion efficiency of 13.3% from the infrared at 1064 nm to DUV at 266 nm. This is the highest output energy ever reported for the DUV sub-nanosecond pulses to the best of our knowledge. Higher energy efficiency of 25.7% can be achieved from 1064 nm to 266 nm when the fundamental energy was reduced to 346 mJ. Furthermore, the DUV generations using LBO and typical β-BaB2O4 (BBO) crystals were compared regarding the energy efficiency, and the effects of the nonlinear absorption are discussed. © 2022 Optica Publishing Group.
  Accession Number: 20220711614367
• Record 168 of
  
  Title:Research on Clustering Algorithm of Hyperspectral Images Based on Fuzzy Kernel P System
  
  Author(s):Qiu, Shi(1); Zhang, Geng(1); Zhang, Miao(1)
  Source: Proceedings - 2022 IEEE/WIC/ACM International Joint Conference on Web Intelligence and Intelligent Agent Technology, WI-IAT 2022  Volume:   Issue:   DOI: 10.1109/WI-IAT55865.2022.00116  Published: 2022  
  Abstract:According to the difficulty of spectral image clustering, an image clustering algorithm is proposed based on fuzzy kernel P system. Through the analysis of fuzzy clustering and kernel clustering, the fuzzy kernel system is built to optimize the organizational P system, and all cells are coordinated to calculate the optimal clustering center in the mapping space to achieve parallel computing. It can reduce the sensitivity of the initial clustering center, improve the global search ability of the algorithm, avoid falling into the local minimum, and improve the clustering performance of the algorithm. © 2022 IEEE.
  Accession Number: 20231914078174