作者机构：
[Qiu, Cheng-Wei; Mei, Shengtao; Mehmood, M.Q.; Siew, S.Y.; Zhang, Lei; Zhang, Tianhang; Danner, Aaron; Hussain, Sajid; Ling, Xiaohui] Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, Singapore;[Qiu, Cheng-Wei; Mei, Shengtao] Graduate School for Integrative Sciences and Engineering, National University of Singapore, Centre for Life Sciences (CeLS), #05-01, 28 Medical Drive, Singapore, Singapore;[Liu, Hong; Huang, Kun; Teng, Jinghua] Institute of Materials Research, Engineering Agency for Science Technology and Research (ASTAR) Innovis, #08-03 2 Fusionopolis Way, Singapore, Singapore;[Ling, Xiaohui] College of Physics and Electronic Engineering, Hengyang Normal University, Hengyang, China;[Zhang, Shuang] School of Physics and Astronomy, University of Birmingham, Birmingham, United Kingdom
通讯机构：
[Qiu, Cheng-Wei] Natl Univ Singapore, Dept Elect & Comp Engn, 4 Engn Dr 3, Singapore 117583, Singapore.;[Qiu, Cheng-Wei] Natl Univ Singapore, Ctr Life Sci CeLS, Grad Sch Integrat Sci & Engn, 05-01,28 Med Dr, Singapore 117456, Singapore.
作者机构：
[Zhou, Xinxing; Liu, Yachao; Luo, Hailu; Shu, Weixing; Ling, Xiaohui; Wen, Shuangchun; Fan, Dianyuan; Chen, Shizhen] Laboratory for Spin Photonics, School of Physics and Electronics, Hunan University, Changsha, 410082, China;[Ling, Xiaohui; Yi, Xunong; Fan, Dianyuan] SZU-NUS Collaborative Innovation Center for Optoelectronic Science and Technology, Key Laboratory of Optoelectronic Devices, Systems of Ministry of Education and Guangdong Province, Shenzhen University, Shenzhen, 518060, China;[Ling, Xiaohui] Department of Physics and Electronic Information Science, Hengyang Normal University, Hengyang, 421002, China
关键词：
geometric phase;metamaterial;photonic spin Hall effect
摘要：
The photonic spin Hall effect (SHE) in the reflection and refraction at an interface is very weak because of the weak spin-orbit interaction. Here, we report the observation of a giant photonic SHE in a dielectric-based metamaterial. The metamaterial is structured to create a coordinate-dependent, geometric Pancharatnam-Berry phase that results in an SHE with a spin-dependent splitting in momentum space. It is unlike the SHE that occurs in real space in the reflection and refraction at an interface,which results from the momentum-dependent gradient of the geometric Rytov-Vladimirskii-Berry phase. We theorize a unified description of the photonic SHE based on the two types of geometric phase gradient, and we experimentally measure the giant spin-dependent shift of the beam centroid produced by the metamaterial at a visible wavelength. Our results suggest that the structured metamaterial offers a potential method of manipulating spin-polarized photons and the orbital angular momentum of light and thus enables applications in spin-controlled nanophotonics.
关键词：
spin Hall effect of light;spin Hall shift;geometric phase;weak measurements
摘要：
The spin Hall effect (SHE) of light, as an analogue of the SHE in electronic systems, is a promising candidate for investigating the SHE in semiconductor spintronics/valleytronics, high-energy physics and condensed matter physics, owing to their similar topological nature in the spin-orbit interaction. The SHE of light exhibits unique potential for exploring the physical properties of nanostructures, such as determining the optical thickness, and the material properties of metallic and magnetic thin films and even atomically thin two-dimensional materials. More importantly, it opens a possible pathway for controlling the spin states of photons and developing next-generation photonic spin Hall devices as a fundamental constituent of the emerging spinoptics. In this review, based on the viewpoint of the geometric phase gradient, we give a detailed presentation of the recent advances in the SHE of light and its applications in precision metrology and future spin-based photonics.
关键词：
Electronic band structure;Graphene;Doping;Density-functional theory
摘要：
A pathway to open the band gap of graphene by p-n codoping is presented according to the first principles study. Two models are used: Lithium adsorbed on Boron-doped graphene (BC) and Boron-Nitrogen (B/N) codoping into graphene. The stability of Lithium adsorbed on BC is firstly analyzed, showing that the hollow site is the most stable configuration, and there is no energy barrier from some metastable configurations to a stable one. After the p-n codoping, the electronic structures of graphene are modulated to open a band gap with width from 0.0 eV to 0.49 eV, depending on the codoping configurations. The intrinsic physical mechanism responsible for the gap opening is the combination of the Boron atom acting as hole doping and Nitrogen (Lithium) as electron doping. (C) 2011 Elsevier B.V. All rights reserved.
作者机构：
[Xia, Li-Xin] Department of Physics, Henan University of Science and Technology, Luoyang, 471003, China;[Zhang, Deng-Yu; Wang, Xin-Wen] Department of Physics and Electronic Information Science, Hengyang Normal University, Hengyang, 421008, China;[Wang, Zhi-Yong] National Laboratory of Solid State Microstructures, Nanjing University, Nanjing, 210093, China;[Wang, Xin-Wen] Department of Physics, Applied Optics Beijing Area Major Laboratory, Beijing Normal University, Beijing, 100875, China
通讯机构：
[Wang, Xin-Wen] Hengyang Normal Univ, Dept Phys & Elect Informat Sci, Hengyang 421008, Peoples R China.
关键词：
Multipartite entanglement;Quantum-information splitting;Asymmetric distribution
通讯机构：
[Wang, Xin-Wen] Hengyang Normal Univ, Dept Phys & Elect Informat Sci, Hengyang 421008, Peoples R China.
关键词：
Coherent state - Even parity - Linear optical - Multiqubit gates - Non-Linearity - Odd-parity - Orders of magnitude - Photon interactions - Photon numbers - Physical resources - Polarization qubits - Polarized photons - Quantum Information - Ring cavities - Two photon - Two-qubit - Two-qubit gates
摘要：
The cross-Kerr nonlinearity (XKNL) effect can induce efficient photon interactions in principle with which photonic multiqubit gates can be performed using far fewer physical resources than linear optical schemes. Unfortunately, it is extremely challenging to generate giant cross-Kerr nonlinearities. In recent years much effort has been made to perform multiqubit gates via weak XKNLs. However, the required nonlinearity strengths are still difficult to achieve in an experiment. We here propose an XKNL-based scheme for realizing a two-photon polarization-parity gate, a universal two-qubit gate, in which the required strength of the nonlinearity could be orders of magnitude weaker than those required for previous schemes. The scheme utilizes a ring cavity fed by a coherent state as a quantum information bus which interacts with a path mode of the two polarized photons (qubits). The XKNL effect makes the bus pick up a phase shift dependent on the photon number of the path mode. Even when the potential phase shifts are very small they can be effectively measured using photon-number resolving detectors, which accounts for the fact that our scheme can work in the regime of tiny XKNL. The measurement outcome reveals the parity (even parity or odd parity) of the two polarization qubits.
期刊：
Journal of Materials Chemistry C,2015年3(22):5697-5702 ISSN：2050-7526
通讯作者：
Zeng, J
作者机构：
[Zeng, Jing] Department of Physics and Electronic Information Science, Hengyang Normal University, Hengyang, China;[Chen, Ke-Qiu] Department of Applied Physics, School of Physics and Electronics, Hunan University, Changsha, China
通讯机构：
[Zeng, Jing] Hengyang Normal Univ, Dept Phys & Elect Informat Sci, Hengyang 421002, Peoples R China.
关键词：
Armchair graphene nanoribbons - Conductance state - Metal electrodes - Non-equilibrium Green's function - Spin filtering - Spin-down state - Spintronic device - Zigzag graphene nanoribbons
摘要：
Ultraviolet (UV) photodetectors with high responsivity and fast response are crucial for practical applications. Double perovskite Cs2AgBiBr6 has emerged as a promising optoelectronic material due to its excellent physics and photoelectric properties. However, no work is reported based on its film for photodetector applications. Herein, an ITO/SnO2/Cs2AgBiBr6/Au hole‐transport layer free planar heterojunction device is fabricated for photodetector application. The device is self‐powered with two responsivity peaks at 350 and 435 nm, which is suitable for ultraviolet‐A (320–400 nm) and deep‐blue light detecting. A high responsivity of 0.11 A W−1 at 350 nm and a quick response time of less than 3 ms are obtained, which is significantly higher than other semiconductor oxide heterojunction‐based UV detectors. More importantly, the stability is significantly better than most of the hybrid perovskite photodetectors reported so far. Its photocurrent shows no obvious degradation after more than 6 months storage in ambient conditions without any encapsulation. Consequently, the utilization of Cs2AgBiBr6 film is a practical approach for high performance, large‐area lead‐free perovskite photodetector applications. For the mechanism, it is found that photogenerated carriers in Cs2AgBiBr6 film are separated at the Cs2AgBiBr6/SnO2 heterojunction interface by its built‐in field. The low toxicity and high stability of this double perovskite active layer make it very promising for practical applications.
期刊：
JOURNAL OF MATERIALS CHEMISTRY C,2018年6(38):10276-10283 ISSN：2050-7526
通讯作者：
Liu, Zhiwei;Xiao, Lixin;Geng, Hua
作者机构：
[Lv, Fang; Bian, Mengying; Guo, Xuan; Xiao, Lixin; Chen, Zhijian] Peking Univ, State Key Lab Mesoscop Phys, Beijing 100871, Peoples R China.;[Lv, Fang; Bian, Mengying; Guo, Xuan; Xiao, Lixin; Chen, Zhijian] Peking Univ, Dept Phys, Beijing 100871, Peoples R China.;[Geng, Hua] Capital Normal Univ, Dept Chem, Beijing 100048, Peoples R China.;[Xiao, Lixin] Hengyang Normal Univ, Coll Phys & Elect Engn, Hengyang 421008, Peoples R China.;[Duan, Lian] Tsinghua Univ, Dept Chem, Minist Educ, Key Lab Organ Optoelect & Mol Engn, Beijing 100084, Peoples R China.
通讯机构：
[Liu, Zhiwei] Peking Univ, Coll Chem & Mol Engn, State Key Lab Rare Earth Mat Chem & Applicat, Beijing Natl Lab Mol Sci, Beijing 100871, Peoples R China.;[Xiao, Lixin] Peking Univ, State Key Lab Mesoscop Phys, Beijing 100871, Peoples R China.;[Xiao, Lixin] Peking Univ, Dept Phys, Beijing 100871, Peoples R China.;[Xiao, Lixin] Hengyang Normal Univ, Coll Phys & Elect Engn, Hengyang 421008, Peoples R China.;[Geng, Hua] Capital Normal Univ, Dept Chem, Beijing 100048, Peoples R China.
摘要：
Combining rigid twisted spirobifluorene with two strongly electron-withdrawing terpyridine moieties to form a "(A)(n)-D-(A)(n)" structure is an effective way to achieve electron transport materials (ETMs) with high triplet energy, suitable frontier orbital levels, excellent thermal stability and electrochemical stability for long-lived and highly efficient organic light-emitting diodes (OLEDs), 2,2'-di([2,2':6',2 ''-terpyridin]-4'-yl)-9,9'-spirobi[fluorene] (22-TPSF) and 2,7-di([2,2':6',2 ''-terpyridin]-4'-yl)-9,9'-spirobifluorene (27-TPSF), both of which are better than the conventional ETM 1,3,5-tris(N-phenylbenzimidazol-2-yl-benzene (TPBi). In addition, the crystal packing mode in their single crystals undergoes a significant transformation from the sandwich arrangement of 22-TPSF into the brick wall arrangement of 27-TPSF, causing a big difference in electron transport mobility, which changes from 0.012 to 0.104 cm(2) V-1 s(-1) as calculated through density functional theory. This variation leads to a phenomenon where the 22-TPSF based devices display a lower maximum external quantum efficiency of 22.9% and a shorter half-life (T-50) of 173925 hours at an initial luminance of 100 cd m(-2) than the 27-TPSF based devices. These findings highlight the great potential of the ETM structured as "(A)(n)-D-(A)(n)" using the terpyridine and spirobifluorene moieties; moreover, the positional isomerism effect allows remarkable tuning of the electron transport mobility and makes an obvious influence on OLED performance and lifetime.
关键词：
pnictides and chalcogenides;properties of superconductors;effects of pressure;methods of materials synthesis and materials processing
摘要：
The origin of the 40 and 30 K superconducting phases in the metal-intercalated FeSe superconductors is still unclear. We report the synthesis of K-0:3(NH3)(y)(FeSe1-xTex)(2) and K-0:6(NH3)(y)(FeSe1-xTex)(2) with x=0-0.6 by using the liquid ammonia method at room temperature. The superconducting transition temperature T-c of the former remains about 43 K for all the nominal Te content less than 0.3, while that of the latter is about 30 K and obviously decreases with Te doping. Superconductivity disappears for x 0.4 in both systems. Except for the different chemical pressure induced by substitution of Te for Se in both systems, we also observed distinct external pressure effect on superconductivity for both systems, with much more efficiency of suppressing T-c by external pressure in the former system. These dramatic differences of both chemical and external pressure effects on T-c between the 30 and 40 K superconducting phases revealed that the existence of the two superconducting phases can be ascribed to the moderate and negligible coupling between FeSe layers, respectively.
摘要：
We theoretically investigate the Imbert-Fedorov (IF) shifts of a reflected light beam from the dielectric interface containing a planar anisotropic monolayer graphene sheet that is subject to an external perpendicular magnetic field. We calculate and discuss the dependence of the IF shifts on the intensity of the magnetic field, the incidence angle of the beam, and the central frequency of the beam. It is shown that IF shifts can be controlled by modifying the intensity of the magnetic field and the incidence angle without changing the material and the structure of the dielectric interface. Moreover, there exists an optimum nonzero control magnetic field under which the IF shift can reach maximum value. (c) 2018 Optical Society of America
关键词：
Dark soliton;Stripe phase background;Stripe dark soliton
摘要：
We present dark solitons on stripe phase background in a two-component coupled Bose-Einstein condensate. It is demonstrated that there are many different dark soliton profiles, in contrast to the dark solitons reported before. These different profiles are classified qualitatively to four distinctive cases, according to the differences between stripe spatial period and soliton size, and the fluctuation degree of stripe background. The interactions between these different dark solitons are also investigated. These results further enrich our knowledge on dark solitons in ultra-cold atomic systems, and other coupled nonlinear systems. (C) 2018 Elsevier B.V. All rights reserved.
摘要：
Decoherence suppression from disturbance of the environment is an essential task in quantum information processing. We investigate decoherence suppression of a qubit system interacting with a heat bath with phase decoherence by employing the weak measurement (WM) and quantum measurement reversal (QMR) operation. We show explicitly that the qubit decoherence can be efficiently completely suppressed by means of the combination WM and QMR, which is independent of the form of the spectral density of the reservoir and the form of initial input state.
期刊：
Journal of Physics B: Atomic, Molecular and Optical Physics,2013年46(2) ISSN：0953-4075
通讯作者：
Zhan, XG
作者机构：
[Yang, Xiaoxue; Zhan, Xiao-Gui; Si, Liu-Gang] Wuhan National Laboratory for Optoelectronics, School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China;[Zheng, An-Shou] College of Mathematics and Physics, China University of Geosciences, Wuhan 430074, China;[Zhan, Xiao-Gui] Department of Physics and Electronic Information Science, Research Institute of Photoelectricity, Hengyang Normal University, Hengyang 421008, China
作者机构：
[Zhou, Xinxing; Liu, Yachao; Wen, Shuangchun; Luo, Hailu; Shu, Weixing; Ling, Xiaohui] Laboratory for Spin Photonics, College of Physics and Microelectronic Science, Hunan University, Changsha, China;[Luo, Hailu; Ling, Xiaohui; Yi, Xunong] SZU-NUS Collaborative Innovation Center for Optoelectronic Science and Technology, Ministry of Education and Guangdong Province, Shenzhen University, Shenzhen, China;[Ling, Xiaohui] Department of Physics and Electronic Information Science, Hengyang Normal University, Hengyang, China
摘要：
Recent developments in the field of photonic spin Hall effect (SHE) offer new opportunities for advantageous measurement of the optical parameters (refractive index, thickness, etc.) of nanostructures and enable spin-based photonics applications in the future. However, it remains a challenge to develop a tunable photonic SHE with any desired spin-dependent splitting for generation and manipulation of spin-polarized photons. Here, we demonstrate experimentally a scheme to realize the photonic SHE tunably by tailoring the space-variant Pancharatnam-Berry phase (PBP). It is shown that light beams whose polarization with a tunable spatial inhomogeneity can contribute to steering the space-variant PBP which creates a spin-dependent geometric phase gradient, thereby possibly realizing a tunable photonic SHE with any desired spin-dependent splitting. Our scheme provides a convenient method to manipulate the spin photon. The results can be extrapolated to other physical system with similar topological origins.
期刊：
Communications in Theoretical Physics,2009年51(2):247-251 ISSN：0253-6102
通讯作者：
Tang Shi-Qing
作者机构：
[TANG Shi-Qing; XIE Li-Jun] Faculty of Material and Photoelectronic Physics, Xiangtan University;[ZHANG Deng-Yu; ZHAN Xiao-Gui; GAO Feng] Department of Physics and Electronic Information Science, Hengyang Normal University
通讯机构：
[Tang Shi-Qing] Xiangtan Univ, Fac Mat & Photoelect Phys, Xiangtan 411005, Peoples R China.
摘要：
We propose a scheme for realization a quantum Controlled-NOT gate operation using two four-level atoms through a selective atom-cavity interaction in cavity quantum electrodynamics system. In our protocol, the quantum information is encoded on the stable ground states of the two atoms. During the interaction between atoms and single mode vacuum cavity-field, the atomic spontaneous emission is negligible as the large atom-cavity detuning effectively suppresses the spontaneous decay of the atoms. The influences of the dissipation and the deviation of interaction time on fidelity and corresponding success probability of the quantum Controlled-NOT gate and the experimental feasibility of our proposal are also discussed.
期刊：
Results in Physics,2017年7:1485-1486 ISSN：2211-3797
通讯作者：
Yang, ZJ;Yang, ZF
作者机构：
[Li, Jian-Xing; Zhang, Shu-Min; Yang, Zhen-Jun; Li, Xing-Liang] Hebei Normal Univ, Coll Phys & Informat Engn, Hebei Adv Thin Films Lab, Shijiazhuang 050024, Hebei, Peoples R China.;[Dai, Zhi-Ping] Hengyang Normal Univ, Coll Phys & Elect Engn, Hengyang 421002, Peoples R China.;[Yang, Zhen-Feng] Hebei Univ Sci & Technol, Dept Informat Management, Shijiazhuang 050018, Hebei, Peoples R China.
通讯机构：
[Yang, Zhen-Feng] Hebei Univ Sci & Technol, Dept Informat Management, Shijiazhuang 050018, Hebei, Peoples R China.;[Yang, Zhen-Jun] Hebei Normal Univ, Coll Phys & Informat Engn, Hebei Adv Thin Films Lab, Shijiazhuang 050024, Hebei, Peoples R China.
关键词：
Interaction;Anomalous vortex beam;Nonlocal media
摘要：
In this paper, the interactional behaviors of anomalous vortex beams in highly nonlocal media are investigated. An analytical expression describing the interaction is given, and some numerical simulations are carried out to illustrate the interactional characteristics. It is found that two interactional anomalous vortex beams always attract each other, and their evolution is periodical. The influence of different relative phases between two anomalous vortex beams on their interaction is presented in details. (C) 2017 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license
期刊：
Quantum Information Processing,2013年12(2):1065-1075 ISSN：1570-0755
通讯作者：
Wang, XW
作者机构：
[Zhang, Deng-Yu; Xie, Li-Jun; Tang, Shi-Qing; Wang, Xin-Wen] Department of Physics and Electronic Information Science, Hengyang Normal University, Hengyang 421008, China;[Wang, Xin-Wen] Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, Department of Physics, Hunan Normal University, Changsha 410081, China
