摘要：
The entanglement dynamics of three-qubit states coupled to a general XY spin-chain with a three-site interaction environment is investigated. By using negativity as entanglement measure, we find that the entanglement evolution depends on not only the system-environment couplings but also the strength of three-site interaction. In the strong-coupling region, the three-site interaction can remarkably enhance the decay of the entanglement of three-qubit states. However, in the weak-coupling region, the process of disentanglement depends on the strength of the three-site interaction.
期刊：
Review of Scientific Instruments,2011年82(4):043503 ISSN：0034-6748
通讯作者：
Tan, Yanliang
作者机构：
[Tan, Yanliang] Hengyang Normal Univ, Dept Phys & Elect, Hengyang 421008, Hunan, Peoples R China.;[Tan, Yanliang; Xiao, Detao] Univ S China, Sch Nucl Sci & Technol, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Tan, Yanliang] H;Hengyang Normal Univ, Dept Phys & Elect, Hengyang 421008, Hunan, Peoples R China.
摘要：
Several measurements of the radon concentration are performed by RAD7 in the University of South China. We find that 30-40 min is needed for RAD7 for tracing the concentration of the standard radon chamber. There are two reasons. The first is that the sufficient time of air cycle is needed for the radon concentration in internal cell of RAD7 equal to that of the environment; and the second is that the sufficient decay time is needed for the (218)Po concentration in internal cell of RAD7 equal to that of the radon. We used a zeroth order approximation to describe the evolution of the environment radon concentration, and obtained a novel algorithm for quick and continuous tracing the change of radon concentration. The corrected radon concentration obtained through this method is in good agreement with the reference value. This method can be applied to develop and improve the instruments for tracing the change of radon concentration quickly. (C) 2011 American Institute of Physics. [doi:10.1063/1.3572271]
摘要：
This paper offers a novel algorithm to better design LEDs arrays for illumination systems. First, the illuminance distribution of LED arrays is studied through theoretical analysis. Second, we present the algorithm criterion and steps. And finally, we use computer to simulate and verify this method. The results show that the illumination uniformity is significantly affected by the spacing of each light in the LED array. The analysis method presented here in this thesis can be usefully applied in LED in the illumination engineering.
期刊：
Physica E-Low-Dimensional Systems & Nanostructures,2011年44(3):696-699 ISSN：1386-9477
通讯作者：
Xiao, Bin-bin
作者机构：
[Xu, Yue-bing; Xiao, Bin-bin] Hengyang Normal Univ, Dept Phys & Elect Informat Sci, Hengyang 421008, Peoples R China.
通讯机构：
[Xiao, Bin-bin] H;Hengyang Normal Univ, Dept Phys & Elect Informat Sci, Hengyang 421008, Peoples R China.
摘要：
Disordered CdSe nanowires have been successfully grown on silicon substrates by Au-catalyzed vaporliquidsolid (VLS) mechanism. Scanning electron microscopy (SEM) reveals that the as-prepared products consist of a large quantity of 1D nanowire disordered predominantly perpendicular to the surface of the substrate. A plausible formation mechanism of disordered CdSe nanowires is proposed here. X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) confirm on their hexagonal wurtzite crystallite structure. An intense red near-band edge emission (702 nm) is observed based on room temperature photoluminescence measurements of individual nanowire. This kind of CdSe nanostructures may be used in optoelectronics devices in the near future.
作者机构：
[龙文] Guizhou Key Laboratory of Economics System Simulation, Guizhou College of Finance and Economics, Guiyang 550004, China;[梁昔明; Li, Zhaohui; 龙文] School of Information Science and Engineering, Central South University, Changsha 410083, China;[龙祖强] Department of Physics and Electronics Information Science, Hengyang Normal College, Hengyang 421008, China
通讯机构：
[Long, W.] G;Guizhou Key Laboratory of Economics System Simulation, Guizhou College of Finance and Economics, China
作者机构：
[龙文] Guizhou Key Laboratory of Economics System Simulation, Guizhou College of Finance and Economics, Guiyang 550004, China;[龙祖强] Department of Physics and Electronic Information Science, Hengyang Normal College, Hengyang 421008, China;[梁昔明; 龙文; Li, Zhao-Hui] School of Information Science and Engineering, Central South University, Changsha 410083, China
通讯机构：
Guizhou Key Laboratory of Economics System Simulation, Guizhou College of Finance and Economics, China
作者机构：
Department of Physics and Electronic Information Science, Hengyang Normal University, Hengyang 421008, China;[WANG; ZHANG; ZHAN; XIE; CHEN; TANG] 衡阳师范学院
关键词：
quantum;information;THREE-LEVEL;ATOM;BIMODAL;cavity;ENTANGLED;state;quantum information;three-level atom;bimodal cavity;entangled state
摘要：
A simple scheme is presented for generating four-photon entangled states with interaction between a three-level atom and two bimodal cavities.In the proposed protocol,the quantum information is encoded on Fock states of the cavity fields.The detection of the atom can collapse the cavity made/wave function to the desired state.The experimental feasibility of our proposal is also discussed.
期刊：
Solar Energy,2011年85(10):2551-2559 ISSN：0038-092X
通讯作者：
Yang, Wenji
作者机构：
[Wang, Yanguo; Yu, Hongchun; Yang, Wenji] Hunan Univ, Coll Phys & Microelect Sci, Micronano Technol Res Ctr, Changsha 410082, Hunan, Peoples R China.;[Wan, Qing; Tang, Jianping; Su, Yingbing] Hunan Univ, Minist Educ, Key Lab Micronano Optoelect Devices, Changsha 410082, Hunan, Peoples R China.;[Tang, Jianping] Hengyang Normal Univ, Dept Phys & Elect Sci, Hengyang 422008, Peoples R China.
通讯机构：
[Yang, Wenji] H;Hunan Univ, Coll Phys & Microelect Sci, Micronano Technol Res Ctr, Changsha 410082, Hunan, Peoples R China.
关键词：
Thin film silicon solar cell;Anti-reflection;Light trapping;Omnidirectionality
摘要：
A theoretical model for an all-in-one thin film silicon solar cell (TFSSC) design with the anti-reflection (AR) coatings, the transparent electrodes, the silicon and the back reflective coatings all deposited on one piece of glass is proposed and the optical performance for the design is numerically simulated. The calculated average reflectance over the wavelength range of 0.4-1.0 mu m and incident angles from 0 degrees to 75 degrees for the optimized dual-AR coatings as a whole is 3.67% - ranking among the lowest values for current AR coatings on silicon solar cells. Furthermore, the spectrum-averaged absorptance (SAA) in the 5-mu m-thick cell in the 0.3-1.2 mu m wavelength range decreases only by 2.58% when the incident angle varies from 0 degrees to 75 degrees, clearly showing the omnidirectional characteristics of the dual-AR coatings. With reasonable assumption of the internal quantum efficiency (near unity), the 5-mu m cell produces a spectrum averaged external quantum efficiency (EQE) of 81.4% at 75 degrees angle of incidence - 6.7% larger than the experiment result of the best planar bulk cell. Under equal sunshine conditions, TFSSCs generally give higher output voltages than their bulk counterpart if equal light absorption is assumed, so the 5-mu m cell has the potential to reach the highest experimental conversion efficiency of the best planar bulk cell. By using a special mathematical technique, we are able to prove the angle-dependent absorption curves in the longer wavelength region tend to converge to a small neighborhood of the upper limit irrespective of significant differences between the transmission profiles. This indicates the AR requirement in the longer wavelength region can be significantly relaxed. (C) 2011 Elsevier Ltd. All rights reserved.
