2023
2023
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Record 505 of
Title:Ultrafast Optomechanical Strain in Layered GeS
Author(s):Luo, Duan(1,2,3,4); Zhang, Baiyu(5); Sie, Edbert J.(4,6); Nyby, Clara M.(7); Fan, Qingyuan(1,4); Shen, Xiaozhe(2); Reid, Alexander H.(2); Hoffmann, Matthias C.(2); Weathersby, Stephen(2); Wen, Jianguo(8); Qian, Xiaofeng(5); Wang, Xijie(2); Lindenberg, Aaron M.(1,4,9)Source: Nano Letters Volume: 23 Issue: 6 Article Number: null DOI: 10.1021/acs.nanolett.2c05048 Published: March 22, 2023Abstract:Strong coupling between light and mechanical strain forms the foundation for next-generation optical micro- and nano-electromechanical systems. Such optomechanical responses in two-dimensional materials present novel types of functionalities arising from the weak van der Waals bond between atomic layers. Here, by using structure-sensitive megaelectronvolt ultrafast electron diffraction, we report the experimental observation of optically driven ultrafast in-plane strain in the layered group IV monochalcogenide germanium sulfide (GeS). Surprisingly, the photoinduced structural deformation exhibits strain amplitudes of order 0.1% with a 10 ps fast response time and a significant in-plane anisotropy between zigzag and armchair crystallographic directions. Rather than arising due to heating, experimental and theoretical investigations suggest deformation potentials caused by electronic density redistribution and converse piezoelectric effects generated by photoinduced electric fields are the dominant contributors to the observed dynamic anisotropic strains. Our observations define new avenues for ultrafast optomechanical control and strain engineering within functional devices. ? 2023 American Chemical Society.Accession Number: 20231113741491 -
Record 506 of
Title:Colloidal Directional Structures at a Nematic Liquid Crystal–Air Interface
Author(s):Wang, Nan(1,2,3); Evans, Julian(2); Li, Chenxi(4); Pergamenshchik, Victor M.(5,6); He, Sailing(1,2,7)Source: arXiv Volume: null Issue: null Article Number: null DOI: 10.48550/arXiv.2308.06865 Published: August 13, 2023Abstract:We present a variety of structures formed by colloidal droplets at a nematic liquid crystal–air interface, where the elastic dipole-dipole, quadrupole-quadrupole, and dipole-quadrupole interactions are all essentially involved. The colloidal structures observed not only include chains with kinks or clusters, but also comprise directional structures, such as directional chains and branches, whose direction is associated with the tilting director in the liquid crystal layer. The dipole-quadrupole interaction, originating from the polydispersity of the droplets, plays a central role for the formation of these directional structures. Clusters consisting of directional branches and chains are also observed and found to be fractal statistically. ? 2023, CC BY-NC-ND.Accession Number: 20230289683 -
Record 507 of
Title:The bound state in the continuum in flexible terahertz metasurfaces enabled sensitive biosensing
Author(s):Qiu, Dan(1,2); Sun, Shuai(1); Cheng, Xuelan(1); Jin, Xiaoyu(1); Qiao, Yutong(1); Zhang, Wei(1,2); Yang, Dexing(2); Chen, Xianzhong(3); Li, Zeren(1); Li, Jia(1); Yao, Jianquan(1,4)Source: Physical Chemistry Chemical Physics Volume: 25 Issue: 33 Article Number: null DOI: 10.1039/d3cp02414h Published: August 4, 2023Abstract:The combination of a flexible device and novel electromagnetic resonances offers new dimensions to manipulate electromagnetic waves and promises new device functionalities. In this study, we experimentally demonstrate a flexible metasurface that can support the bound state in the continuum (BIC) in the terahertz regime. The metasurface consists of toroidal dipole resonant units on top of the flexible polyimide substrate, which can support a terahertz Friedrich-Wintgen BIC resonance, and the resonance characteristics can be tuned by changing the parameters of the coupling unit among two resonant modes. The BIC resonances under different bending conditions are analyzed and compared, showing decent mechanical robustness. The sensing application is demonstrated by combining Fetal Bovine Serum with the flexible BIC metasurface. The measured minimum detectable concentration is 0.007 mg mL?1. Benefiting from the mechanical flexibility and BIC resonance characteristics, our approach can effectively manipulate terahertz waves and have potential applications in the realization of multifunctional and flexible photonic devices. ? 2023 The Royal Society of Chemistry.Accession Number: 20233614674999 -
Record 508 of
Title:Hybrid integrated narrow-linewidth semiconductor lasers
Author(s):Li, Baoshuai(1); Wang, Weiqiang(2); Yang, Honglei(3); Liu, Hao(4); Chu, Sai T.(5); Little, Brent(2); Song, Yuxia(1); Guan, Boren(1); Zhang, Wenfu(2); Li, Mingyu(1)Source: Applied Optics Volume: 62 Issue: 14 Article Number: null DOI: 10.1364/AO.486492 Published: May 10, 2023Abstract:Integrated narrow-linewidth lasers are the key devices in compact coherent optical systems of metrology, sensing, and optical microwave generation. Here, we demonstrate a hybrid integrated laser based on an optical negative feedback scheme. The laser is composed of a commercial distributed feedback (DFB) laser diode and an on-chip micro-resonator with a Q-factor of 0.815 million. The feedback optical field is coupled back to the laser cavity through the back facet. Therefore, the laser can maintain the lasing efficiency of the DFB laser diode. The linewidth of the DFB laser diode is compressed from 2 MHz to 6 kHz, corresponding to the linewidth reduction factor of 25.2 dB. The theoretical result shows that the laser performance still has a huge improvement margin through precise control of the detuning between laser frequency and the micro-resonator, as well as the phase delay of the feedback optical field. The hybrid narrow-linewidth laser diode has wide application prospects in coherent optical systems benefitting from the low cost and volume productivity. ? 2023 Optica Publishing Group.Accession Number: 20232614291616 -
Record 509 of
Title:Nonthermal Ultrafast Optical Control of Magnetization Dynamics by Linearly Polarized Light in Metallic Ferromagnet
Author(s):Shi, Jingyu(1,2); Zhao, Zirui(1); Dai, Yu(3); He, Jiang(1); Li, Tao(1); Liang, En(1); Wang, Jun(1); Ni, Gang(1); Sheng, Chuanxiang(1); Wu, Di(4); Zhou, Shiming(3); Chen, Liangyao(1); Zhao, Haibin(1,5)Source: Advanced Science Volume: 10 Issue: 6 Article Number: 2205903 DOI: 10.1002/advs.202205903 Published: February 24, 2023Abstract:Coherent optical control of the magnetization in ferromagnetic (FM) mediums using ultrafast nonthermal effect paves a promising avenue to improve the speed and repetition rate of the magnetization manipulation. Whereas previously, only heat-induced or helicity-dependent magnetization dynamics are demonstrated in metallic ferromagnets. Here, the linearly-polarized light control of magnetization is demonstrated in FM Co coupled with ferroelectric (FE) BiFeO3 by tuning the light polarization direction. It is revealed that in the Co/BiFeO3 heterostructure excited by femtosecond laser pulses, the magnetization precession amplitude follows a sinusoidal dependence on the laser polarization direction. This nonthermal control of coherent magnetization rotation is attributed to the optical rectification effect in the BiFeO3 layer, which yields a FE polarization depending on the light polarization, and the subsequent modulation of magnetic energy in Co by the electrostriction-induced strain. This work demonstrates an effective route to nonthermally manipulate the ultrafast magnetization dynamics in metallic ferromagnets. ? 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.Accession Number: 20230113342899 -
Record 510 of
Title:Activities to Promote the Moon as an Absolute Calibration Reference
Author(s):Jing, Zhenhua(1); Hu, Xiuqing(2,3); Wang, Yang(4); Wu, Ronghua(2,3); Chen, Lin(2,3); Zhang, Lu(2,3); Huang, Yu(5); Wang, Shuang(6); Li, Shuang(1); Zhang, Peng(2,3)Source: Remote Sensing Volume: 15 Issue: 9 Article Number: 2431 DOI: 10.3390/rs15092431 Published: May 2023Abstract:The accuracy and consistency of Earth observation (EO) instrument radiometric calibration is a fundamental prerequisite for achieving accurate results and delivering reliable predictions. Frequent calibration and validation (Cal/Val) activities are needed during the instrument’s lifetime, and this procedure is often extended to historical archives. Numerous satellites in orbit and proposed future missions have incorporated lunar observation into their vicarious calibration components over recent years, facilitated by the extreme long-term photometric stability of the Moon. Since the birth of the first lunar calibration reference model, lunar-dependent calibration techniques have developed rapidly, and the application and refinement of the lunar radiometric model have become a welcome research focus in the calibration community. Within the context of the development of lunar observation activities and calibration systems globally, we provide a comprehensive review of the activities and results spawned by treating the Moon as a reference for instrument response and categorize them against the understanding of lunar radiometric reference. In general, this appears to be a process of moving from data to instruments, then back into data, working towards a stated goal. Here we highlight lunar radiometric models developed by different institutions or agencies over the last two decades while reporting on the known limitations of these solutions, with unresolved challenges remaining and multiple lunar observation plans and concepts attempting to address them from various perspectives, presenting a temporal development. We also observe that the methods seeking uncertainty reduction at this stage are rather homogeneous, lacking the combination of approaches or results from lunar surface studies conducted by many spacecraft missions, and joint deep learning methods to extract information. The factors that influence the accuracy of the measurement irradiance may be regulated when practical models arrive. As a central element in lunar calibration, the development of an absolute radiometric datum helps to better understand the Earth system. ? 2023 by the authors.Accession Number: 20232114121931 -
Record 511 of
Title:Spectromicroscopy of Nanoscale Materials in the Tender X-Ray Regime Enabled by a High Efficient Multilayer-Based Grating Monochromator
Author(s):Werner, Stephan(1); Guttmann, Peter(1); Siewert, Frank(1); Sokolov, Andrey(1); Mast, Matthias(1); Huang, Qiushi(2); Feng, Yufei(2); Li, Tongzhou(2); Senf, Friedmar(3); Follath, Rolf(4); Liao, Zhohngquan(5); Kutukova, Kristina(5); Zhang, Jian(6); Feng, Xinliang(7); Wang, Zhan-Shan(2); Zschech, Ehrenfried(5,8); Schneider, Gerd(1,9)Source: Small Methods Volume: 7 Issue: 1 Article Number: 2201382 DOI: 10.1002/smtd.202201382 Published: January 20, 2023Abstract:The combination of near edge X-ray absorption spectroscopy with nanoscale X-ray imaging is a powerful analytical tool for many applications in energy technologies, catalysis, which are critical to combat climate change, as well as microelectronics and life science. Materials from these scientific areas often contain key elements, such as Si, P, S, Y, Zr, Nb, and Mo as well as lanthanides, whose X-ray absorption edges lie in the so-called tender photon energy range 1.5–5.0?keV. Neither conventional grazing incidence grating nor crystal monochromators have high transmission in this energy range, thereby yielding the tender photon energy gap. To close this gap, a monochromator setup based on a multilayer coated blazed plane grating and plane mirror is devised. The measurements show that this novel concept improves the photon flux in the tender X-ray regime by two-orders-of-magnitude enabling previously unattainable laboratory and synchrotron-based studies. This setup is applied to perform nanoscale spectromicroscopy studies. The high photon flux provides sufficient sensitivity to obtain the electronic structure of Mo in platinum-free MoNi4 nanoparticles for electrochemical energy conversion. Additionally, it is shown that the chemical bonding of nano-structures in integrated circuits can be distinguished by the electronic configuration at the Si-K edge. ? 2022 The Authors. Small Methods published by Wiley-VCH GmbH.Accession Number: 20224813199601 -
Record 512 of
Title:High-aspect-ratio dielectric pillar with nanocavity backed by metal substrate in the infrared range
Author(s):Lu, Xiaoyuan(1); Tognazzi, Andrea(2,3); Cino, Alfonso C.(2); Angelis, Costantino De(3,4); Xu, Gang(5); Zhang, Tongyi(6,7); Shishmarev, Dmitry(8)Source: Optics Express Volume: 31 Issue: 23 Article Number: null DOI: 10.1364/OE.506208 Published: November 6, 2023Abstract:We investigated absorption and field enhancements of shallow nanocavities on top of high-aspect-ratio dielectric pillars in the infrared range. The structure includes a high-aspect-ratio nanopillar array of high refractive index, with nano-cavities on top of the pillars, and a metal plane at the bottom. The enhancement factor of electric field intensity reaches 3180 in the nanocavities and peak absorption reaches 99%. We also investigated the finite-size effect of the presented structure to simulate real experiments. Due to its narrow absorption bandwidth 3.5 nm, it can work as a refractive index sensor with sensitivity 297.5 nm/RIU and figure of merit 85. This paves the way to directly control light field at the nanoscales in the infrared light range. The investigated nanostructure will find applications in multifunctional photonics devices such as chips for culturing cells, refractive index sensors, biosensors of single molecule detection and nonlinear sensors. ? 2023 OSA - The Optical Society. All rights reserved.Accession Number: 20234815137357 -
Record 513 of
Title:The Solar Upper Transition Region Imager (SUTRI) onboard the SATech-01 satellite
Author(s):Bai, Xianyong(1,2); Tian, Hui(1,3,8); Deng, Yuanyong(1,2); Wang, Zhanshan(4); Yang, Jianfeng(5); Zhang, Xiaofeng(6); Zhang, Yonghe(6); Qi, Runze(4); Wang, Nange(5); Gao, Yang(6); Yu, Jun(4); He, Chunling(4); Shen, Zhengxiang(4); Shen, Lun(5); Guo, Song(5); Hou, Zhenyong(3); Ji, Kaifan(7); Bi, Xingzi(6); Duan, Wei(1); Yang, Xiao(1); Lin, Jiaben(1); Hu, Ziyao(1); Song, Qian(1,2); Yang, Zihao(3); Chen, Yajie(3); Qiao, Weidong(5); Ge, Wei(5); Li, Fu(5); Jin, Lei(5); He, Jiawei(5); Chen, Xiaobo(5); Zhu, Xiaocheng(6); He, Junwang(6); Shi, Qi(6); Liu, Liu(6); Li, Jinsong(6); Xu, Dongxiao(6); Liu, Rui(6); Li, Taijie(6); Feng, Zhenggong(6); Wang, Yamin(6); Fan, Chengcheng(6); Liu, Shuo(6); Guo, Sifan(1,2); Sun, Zheng(3); Wu, Yuchuan(1,2); Li, Haiyu(3); Yang, Qi(2,3); Ye, Yuyang(1,2); Gu, Weichen(8); Wu, Jiali(8); Zhang, Zhe(4); Yu, Yue(4); Ye, Zeyi(4); Sheng, Pengfeng(4); Wang, Yifan(4); Li, Wenbin(4); Huang, Qiushi(4); Zhang, Zhong(4)Source: arXiv Volume: null Issue: null Article Number: null DOI: 10.48550/arXiv.2303.03669 Published: March 7, 2023Abstract:The Solar Upper Transition Region Imager (SUTRI) onboard the Space Advanced Technology demonstration satellite (SATech-01), which was launched to a sun-synchronous orbit at a height of ～500 km in July 2022, aims to test the on-orbit performance of our newly developed Sc/Si multi-layer reflecting mirror and the 2k×2k EUV CMOS imaging camera and to take full-disk solar images at the Ne VII 46.5 nm spectral line with a filter width of ～3 nm. SUTRI employs a Ritchey-Chrétien optical system with an aperture of 18 cm. The on-orbit observations show that SUTRI images have a field of view of ～ 41.6’×41.6’ and a mod-SUTRI images is 30 s and the solar observation time is about 16 hours each day because the earth eclipse time accounts for about 1/3 of SATech-01’s orbit period. Approximately 15 GB data is acquired each day and made available online after processing. SUTRI images are valuable as the Ne VII 46.5 nm line is formed at a temperature regime of ～0.5 MK in the solar atmosphere, which has rarely been sampled by existing solar imagers. SUTRI observations will establish connections between structures in the lower solar atmosphere and corona, and advance our understanding of various types of solar activity such as flares, filament eruptions, coronal jets and coronal mass ejections. ? 2023, CC BY.Accession Number: 20230083923 -
Record 514 of
Title:Atom-referenced on-chip soliton microcomb
Author(s):Niu, Rui(1,2); Wan, Shuai(1,2); Hua, Tian-Peng(2); Wang, Wei-Qiang(3,4); Wang, Zheng-Yu(1,2); Li, Jin(1,2); Wang, Zhu-Bo(1,2); Li, Ming(1,2); Shen, Zhen(1,2); Sun, Y.R.(2,5); Hu, Shui-Ming(2,5); Little, B.E.(3,4); Chu, S.T.(6); Zhao, Wei(3,4); Guo, Guang-Can(1,2); Zou, Chang-Ling(1,2); Xiao, Yun-Feng(7); Zhang, Wen-Fu(3,4); Dong, Chun-Hua(1,2)Source: arXiv Volume: null Issue: null Article Number: null DOI: null Published: April 3, 2023Abstract:For the applications of the frequency comb in microresonators, it is essential to obtain a fully frequency-stabilized microcomb laser source. Here, we demonstrate an atom-referenced stabilized soliton microcomb generation system based on the integrated microring resonator. The pump light around 1560.48 nm locked to an ultra-low-expansion (ULE) cavity, is frequency-doubled and referenced to the atomic transition of 87Rb. The repetition rate of the soliton microcomb is injection-locked to an atomic-clock-stabilized radio frequency (RF) source, leading to mHz stabilization at 1 seconds. As a result, all comb lines have been frequency-stabilized based on the atomic reference and could be determined with very high precision reaching ～ 18 Hz at 1 second, corresponding to the frequency stability of 9.5 × 10?14. Our approach provides an integrated and fully stabilized microcomb experiment scheme with no requirement of f ? 2f technique, which could be easily implemented and generalized to various photonic platforms, thus paving the way towards the portable and ultraprecise optical sources for high precision spectroscopy. Copyright ? 2023, The Authors. All rights reserved.Accession Number: 20230129264 -
Record 515 of
Title:Multidimensional optical tweezers synthetized by rigid-body emulated structured light
Author(s):Zhu, Liuhao(1); Tai, Yuping(1,2); Li, Hehe(1); Hu, Huajie(1); Li, Xinzhong(1,2); Cai, Yangjian(3,4); Shen, Yijie(5,6)Source: Photonics Research Volume: 11 Issue: 9 Article Number: null DOI: 10.1364/PRJ.490103 Published: September 1, 2023Abstract:Structured light with more extended degrees of freedom (DoFs) and in higher dimensions is increasingly gaining traction and leading to breakthroughs such as super-resolution imaging, larger-capacity communication, and ultraprecise optical trapping or tweezers. More DoFs for manipulating an object can access more maneuvers and radically increase maneuvering precision, which is of significance in biology and related microscopic detection. However, manipulating particles beyond three-dimensional (3D) spatial manipulation by using current all-optical tweezers technology remains difficult. To overcome this limitation, we theoretically and experimentally present six-dimensional (6D) structured optical tweezers based on tailoring structured light emulating rigid-body mechanics. Our method facilitates the evaluation of the methodology of rigid-body mechanics to synthesize six independent DoFs in a structured optical trapping system, akin to six-axis rigid-body manipulation, including surge, sway, heave, roll, pitch, and yaw. In contrast to previous 3D optical tweezers, our 6D structured optical tweezers significantly improved the flexibility of the path design of complex trajectories, thereby laying the foundation for next-generation functional optical manipulation, assembly, and micromechanics. ? 2023 Chinese Laser Press.Accession Number: 20234414984443 -
Record 516 of
Title:Suppression of Gyroscopic Torque Disturbance in High Speed Magnetically Levitated Rigid Rotor Systems Based on Extended State Observer
Author(s):Wang, Can(1,2); Le, Yun(3); Zheng, Shiqiang(4); Han, Bangcheng(5); Dong, Baotian(4); Chen, Qi(6)Source: IEEE/ASME Transactions on Mechatronics Volume: 28 Issue: 3 Article Number: null DOI: 10.1109/TMECH.2022.3224391 Published: June 1, 2023Abstract:The gyroscopic torque disturbances generated by base motion directly affects the stability of the high speed magnetically levitated centrifugal compressor (MLCC). This article explores a disturbance suppression method for the high-speed magnetically levitated rotor (MLR) system based on improved linear extended state observer (LESO). Firstly, the model of the high-speed MLR system with base motion is established, and the characteristics of the gyroscopic torque disturbance are analyzed. Then, a LESO with adaptive notch filter is designed for disturbance estimation and compensation of the magnetic bearing, and its convergence performance and disturbance tracking speed are deduced. Furthermore, due to the gain attenuation introduced by LESO, an innovative gain compensator is utilized to improve controller dynamic performance. Finally, simulation and experimental results demonstrate that the proposed method can effectively reject the gyroscopic torque disturbances in high speed MLCC. ? 1996-2012 IEEE.Accession Number: 20225113274251