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science china(physics,Mechanics & Astronomy) 2024年第2期67卷 40-58页

作者： Jia-Yan Jiang Qian chen Yunqi Liu Yu Tian wei Xiong cheng-yong Zhang bin Wang Department of physics and Siyuan Laboratory Jinan UniversityGuangzhou 510632China School of Physical sciences University of Chinese Academy of SciencesBeijing 100049China center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China Institute of Theoretical physics Chinese Academy of SciencesBeijing 100190China School of physics and Optoelectronics South China University of TechnologyGuangzhou 510641China School of aeronautics and astronautics Shanghai Jiao Tong UniversityShanghai 200240China

We investigated the critical dynamical scalarization and descalarization of black holes within the framework of the EinsteinMaxwell-scalar theory featuring higher-order coupling *** the critical scalarization and descalarization displayed first-order phase *** examining the nonlinear dynamics near the threshold,we always observed critical solutions that are linearly unstable static scalarized black *** critical dynamical scalarization and descalarization share certain similarities with the typeⅠcritical gravitational ***,their initial configurations,critical solutions,and final outcomes differ *** provide further insights into the dynamical results,we conducted a comparative analysis involving static solutions and perturbative analysis.

关键词： black hole(de)scalarization dynamical critical behavior attractor

A tunable dual-narrowband band-pass filter using plasma quantum well structure

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Chinese physics B 2014年第6期23卷 370-374页

作者：戴燚刘少斌王身云孔祥鲲陈忱 college of Electronic and Information Engineering Nanjing University of Aeronautics & Astronautics college of Electronic and Information Egineering Nanjing University of Information Science and Technology

A tunable dual-narrowband pass-band filter is designed. A one-dimensional photonic crystal （1D PC） is comprised of alternate dielectric layer and vacuum layer. Two quantum wells （QWs） as defects can be constructed by sandwiching two plasma slabs symmetrically in the 1D PC, and a dual-narrowband pass-band filter is formed. The conventional finite- difference time-domain （FDTD） method and piecewise linear current density recursive convolution （PLCDRC）-FDTD method are applied to the dielectric and plasma, respectively. The simulation results illustrate that the dual-narrowband frequencies can be tuned by changing the plasma frequency. The pass band interval and the half-power bandwidths （-3-dB band widths） are related to the space interval between two QWs.

关键词： quantum well dual-narrowband pass-band filter plasma

Characterization of the negative thermal expansion material Zr_(1-x)Hf_xW_2O_8

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Rare Metals 2003年第2期22卷 107-111页

作者： SHENRong WANGCong WANGTianmin DONGcheng chenHong LIANGJingkui SchoolofMatgfialsandMetallurgicalEngineering KunmingUniversityofScienceandTechnologyKunming650093China centerofMaterialphysicsandChemistry SchoolofSciencesBeijingUniversityofAeronauticsandAstronauticsBeijing100083China Instituteofphysics ChineseAcademyofScienceBeijing100080China

The oxide ZrW_2O_8 displays unusual property of isotropic negative thermalexpansion in a large wide temperature range, which makes it have a number of important potentialapplications. The cubic Zr_(1-x)Hf_xW_2O_8 (x velence 0,0.3, 0.5, 0.7, and 1.0) were synthesized bystandard solid state reaction technique. The high and low temperature X-ray diffraction analysisindicate that the substitution of the Hf^(4+) for Zr^(4+) only leads to reducing the latticeconstants, and the changes of negative thermal expansion coefficients are not obvious. The linearexpansion coefficients of Zr_(1-x)Hf_xW_2O_8 (x velence 0,0.3, 0.5, 0.7, and 1.0) are about -6 X 10^(-6) K^(-1) in the temperature range of 298 to 973 K, while that of Zr_(0.5)Hf_(0.5)W_2O_8 is -9.6X 10^(-6) K_(-1) from 83 to 298 K. The phase transition temperatures from alpha-ZrW_2O_8 tobeta-ZrW_2O_8 structure were also determined by X-ray diffraction method. Thermogravimetric analysis(TGA) exhibits that Zr_(1-x)Hf_xW_2O_8 is not hygroscopic in air.

关键词： inorganic non-metallic materials negative thermal expansion X-raydiffraction Zr_(1-x)Hf_xW_2O_8

Spin-glass like behaviors in La_(1-x)Tb_xMnO_3 perovskite

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science china(physics,Mechanics & Astronomy) 2009年第12期52卷 1893-1897页

作者： ZHANG YingTang1,2,3,WANG ChunChang2,4,LIU weibin1,WANG Zhong3,LU Huibin2 & chen ZiYu1 1 Department of physics,Beijing university of aeronautics and astronautics,Beijing 100191 2 Institute of physics & center for Condensed Matter physics,Chinese Academy of sciences,Beijing 100190 3 School of Material science & Engineering,Shaanxi university of technology,Hanzhong 723003 4 Institute of Superconducting and Electronic materials,Wollongong university,Northfield Ave,Gwynneville,NSW 2522,Australia 1. Department of physics Beijing University of Aeronautics and Astronautics Beijing 100191 China 2. Institute of physics & center for Condensed Matter physics Chinese Academy of Sciences Beijing 100190 China 3. School of Material science & Engineering Shaanxi University of Technology Hanzhong 723003 China 4. Institute of Superconducting and Electronic materials Wollongong University Northfield Ave Gwynneville NSW 2522 Australia

A series of samples of La1-xTbxMnO3 (0≤x≤0.15) are prepared. The static and dynamic magnetizations of La1-xTbxMnO3 have been investigated. The results indicate that the spins with the short-range order are frozen into random direction at low enough temperatures which leads to the samples exhibiting the spin-glass like behavior. It is considered that the spin-glass like behavior originates from the competition between ferromagnetic double exchange among Mn3+ and Mn2+ and antiferromagnetic superex-change among Mn3+ and Mn3+,as well as Tb3+ and Tb3+.

关键词： La1-xTbxMnO3 spin-glass-like behavior short-range order

Seeing at a distance with multicore fibers

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Opto-Electronic Advances 2024年第7期7卷 39-49页

作者： Haogong Feng Xi chen Runze Zhu Yifeng Xiong Ye chen Yanqing Lu Fei Xu National Laboratory of Solid State Microstructures College of Engineering and Applied Sciencesand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China college of physics MIIT Key Laboratory of Aerospace Information Materials and PhysicsState Key Laboratory of Mechanics and Control for Aerospace StructuresNanjing University of Aeronautics and AstronauticsNanjing 211106China

Images and videos provide a wealth of information for people in production and *** most digital information is transmitted via optical fiber,the image acquisition and transmission processes still rely heavily on electronic *** development of all-optical transmission networks and optical computing frameworks has pointed to the direction for the next generation of data transmission and information ***,we propose a high-speed,low-cost,multiplexed parallel and one-piece all-fiber architecture for image acquisition,encoding,and transmission,called the Multicore Fiber Acquisition and Transmission Image System(MFAT).Based on different spatial and modal channels of the multicore fiber,fiber-coupled self-encoding,and digital aperture decoding technology,scenes can be observed directly from up to 1 km *** expansion of capacity provides the possibility of parallel coded transmission of multimodal high-quality *** requires no additional signal transmitting and receiving *** all-fiber processing saves the time traditionally spent on signal conversion and image pre-processing(compression,encoding,and modulation).Additionally,it provides an effective solution for 2D information acquisition and transmission tasks in extreme environments such as high temperatures and electromagnetic interference.

关键词： long-distance fiber imaging image transmission parallel transmission all-optical encoding multicore fiber

Black hole images:A review

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science china(physics,Mechanics & Astronomy) 2023年第6期66卷 101-117页

作者： Songbai chen Jiliang Jing wei-Liang Qian bin Wang Department of physics Synergetic Innovation Centerfor Quantum Effects and ApplicationsHunan Normal UniversityChangsha 40081China center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China Escola de Engenharia de Lorena Universidade de Sao PauloSao Paulo 12602-810Brazil Faculdade de Engenharia de Guaratingueta Universidade Estadual PaulistaSao Paulo 12516-410Brazil School of aeronautics and astronautics Shanghai Jiao Tong UniversityShanghai 200240China

In recent years,unprecedented progress has been achieved regarding black holes’observation through the electromagnetic *** images of the supermassive black holes M87*and Sgr A*released by the Event Horizon Telescope(EHT)Collaboration provided direct visual evidence for their existence,which has stimulated further studies on various aspects of the compact celestial ***,the information stored in these images provides a new way to understand the pertinent physical processes that occurred near the black holes,to test alternative theories of gravity,and to furnish insight into fundamental *** this review,we briefiy summarize the recent developments on the *** particular,we elaborate on the features and formation mechanism of black hole shadows,the properties of black hole images illuminated by the surrounding thin accretion disk,and the corresponding polarization *** potential applications of the relevant studies are also addressed.

关键词： black hole shadow accretion disk polarization image

Towards growth of pure AB-stacked bilayer graphene single crystals

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Nano Research 2024年第5期17卷 4616-4621页

作者： Xiaowen Zhang Tao Zhou Yunlong Ren Zuo Feng Ruixi Qiao Qinghe Wang bin Wang Jinxia Bai Muhong Wu zhilie Tang Xu Zhou Kaihui Liu Xiaozhi Xu Guangdong Basic Research center of Excellence for Structure and Fundamental Interactions of Matter Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum MaterialsSchool of PhysicsSouth China Normal UniversityGuangzhou 510006China Guangdong-Hong Kong Joint Laboratory of Quantum Matter School of PhysicsSouth China Normal UniversityGuangzhou 510006China Physical science and Engineering Division King Abdullah University of Science and TechnologyThuwal 23955–6900Saudi Arabia State Key Laboratory for Mesoscopic physics Frontiers Science Center for Nano-optoelectronicsSchool of PhysicsPeking UniversityBeijing 100871China Institute for Frontier science Nanjing University of Aeronautics and AstronauticsNanjing 210094China International Centre for Quantum materials Collaborative Innovation Centre of Quantum MatterPeking UniversityBeijing 100871China Songshan Lake materials Laboratory Institute of PhysicsChinese Academy of SciencesDongguan 523808China

Given its intriguing band structure and unique tunable bandgap,AB-stacked bilayer graphene has great potentials in the applications of high-end electronics,optoelectronics and *** epitaxial growth of AB-stacked single-crystal bilayer graphene films requires a strict AB-stacked lattice,identical orientations and seamless stitching of bilayer graphene ***,the particles inevitably present on the metal surface that produced during high temperature growth would induce random orientations,twisted stacking islands,and uncontrollable multilayers,which is a great challenge to ***,we propose a heat-resisting-box assisted strategy to produce nearly pure AB-stacked bilayer graphene single-crystal films on Cu/Ni(111)*** our technique,the particles on the Cu/Ni(111)surface are effectively eliminated,which greatly minimizes the occurrence of randomly twisted islands and uncontrollable *** as-grown AB-stacked bilayer graphene films show>99%alignment and>99%AB stacking *** work provides a promising method towards the growth of pure AB-stacked bilayer graphene single crystals and would accelerate its device applications.

关键词： bilayer graphene AB stacking uniform growth heat-resisting box

Entropy-modulated and interlayer-doped transition metal layered oxides enable high-energy-density sodium-ion capacitors

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Nano Research 2024年第10期17卷 8785-8793页

作者： Tiansheng Wang Yadong Li Zhengyuan chen Qingshan Liu Jian Lang Langyuan Wu Wendi Dong Zhengyu Ju Hongsen Li Xiaogang Zhang Guihua Yu college of physics Qingdao UniversityQingdao 266071China Jiangsu Key Laboratory of materials and Technologies for Energy Storage College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China materials science and Engineering Program and Walker Department of Mechanical Engineering The University of Texas at AustinAustin 78712USA

In recent years,sodium-ion capacitors have attracted attention due to their cost-effectiveness,high power density and similar manufacturing process to lithium-ion ***,the utilization of oxide electrodes in traditional sodium-ion capacitors restricts their further advancement due to the inherent low operating voltage and electrolyte consumption based on their energy storage *** address these challenges,we incorporated Zn,Cu,Ti,and other elements into Na_(0.67)Ni_(0.33)Mn_(0.67)O_(2) to synthesize P2-type Na_(0.7)Ni_(0.28)Mn_(0.6)Zn_(0.05)Cu_(0.02)Ti_(0.05)O_(2) with a modulated entropy and pillaring *** the synergistic interplay between the interlayer pillar and the entropy modulation within the layers,the material exhibits exceptional toughness,effectively shielding it from detrimental phase transitions at elevated voltage *** a result,the material showcases outstanding kinetic properties and long-term cycling stability across the voltage *** integrating these materials with hierarchical porous carbon nanospheres to form a"rocking chair"sodium-ion capacitor,the hybrid full device delivers a high energy density(171 Wh·kg^(-1))and high power density(5245 W·kg^(-1)),as well as outstanding cycling stability(77% capacity retention after 3000 cycles).This work provides an effective material development route to realize simultaneously high energy and power for next-generation sodium-ion capacitors.

关键词： sodium-ion capacitors entropy modulation high power density long-term cycling layered oxide

Metastable magnetic behavior in La_(0.9)Tb_(0.1)MnO_3

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Rare Metals 2017年第7期36卷 596-600页

作者： wei-bin Liu Ying-Tang Zhang Zi-Yu chen Li-Zhu Liu Sheng-Tao Li Tao-Tao Ai Department of physics Beijing University of Aeronautics and Astronautics School of Material science and Engineering Institute of Functional MaterialShaanxi University of Technology Key Laboratory of Engineering Dielectrics and Its Application Ministry of EducationHarbin University of Science and Technology State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong University

The linear and nonlinear magnetizations of La0.9Tb0.1MnO3 at low temperatures were reported in de- tail. The temperature dependence of magnetization shows peaks at 50, 100 and 150 K, respectively. When LaMnO3 is Tb-doped, its magnetic structure exhibits a canted an- tiparallel spin order. This is different from classical antiferromagnetic （AFM） in which the relaxation behavior takes place at about 150 K. At 50 K, Tb-doped LaMnO3 exhibits canonical spin glass behavior, arising from the competition of exchange and super-exchange between spins. The peak at 100 K shows neither spin glass behavior nor canted AFM behavior. Its peak value increases with frequency increasing, and the transition temperature of the peak shifts to higher temperatures with frequency increasing. The study of aging behavior at 100 K shows a periodical variable metastability, which is ascribed to the competition between ferromagnetic （FM）-, AFM- and sinusoidal-order interactions. This work should shed a light on understanding the complex magnetic structure of the perovskite oxides.

关键词： La0.9Tb0.1MnO3 Relaxation behavior Metastability