检索结果-南通市图书馆

Dense Coding with Multi-Atom Entanglement Channel in Cavity QED

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2007年第1期24卷 11-14页

作者：汪新文刘翔汪志勇 Department of Electronic Engineering and Physics Hunan University of Science and Engineering Yongzhou 4251000 College of Physics and Information Science Hunan Normal University Changsha 410081 Department of Physics Hengyang Normal University Hengyang 421008

Dense coding of multi-atom entangled states in cavity QED is studied. If the quantum channel is generalized GHZ states, dense coding can be directly realized in a simply way. As for the partially entangled pure states, we propose a feasible protocol for entanglement concentration, and the emciency of information transmitted is calculated. The schemes are insensitive to the cavity decay and the field state, due to the fact that the interaction here is a large-detuned one between atoms and the cavity.

关键词： ATOMS physical & theoretical chemistry QUANTUM theory PHYSICS

Consistency between Itinerant and Local-Moment Pictures for Superconductivity in Alkaline Iron Selenide Superconductors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2014年第6期31卷 199-202页

作者：李海超向圆圆王强华 National Laboratory of Solid State Microstructure and Department of Physics Nanjing University Nanjing 210093

We study the superconducting pairing in an effective one-orbital model for alkaline iron-selenide superconductors. In both itinerant and local-moment pictures, we find that the nearest-neighbor hopping t1 plays a crucial role. The pairing symmetry changes from s-wave to d-wave as t1 is enhanced. For a reasonable t1 relevant to the experiment, the pairing symmetry is s-wave in both pictures, in agreement with the angle-resolved photo-emission. The results resolve the previous theoretical inconsistency in the two pictures.

关键词： ALKALINE solutions RESEARCH SOLUTION (chemistry) SUPERCONDUCTORS -- Magnetic properties SELENIDES -- Synthesis physical & theoretical chemistry MATTER -- Properties

Hawking Radiation of Dirac Field in the Linear Dilaton Black Hole

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2014年第6期31卷 13-15页

作者：李然 Department of Physics Henan Normal University Xinxiang 453007

By studying the perturbation of massless Dirac field in the background of linear dilaton black hole we show that the covariant Dirac equation can be separated into radial and angular equations. The Damour-Ruffini method is applied to derive the spectrum of Hawking radiation for the Dirac field, from which the Hawking temperature can be read off. It is shown that the Hawking temperature is consistent with the result calculated from the surface gravity.

关键词： HAWKING radiation VIRTUAL particles DIRAC function DIRAC formulation LINEAR algebra physical & theoretical chemistry

Above-Threshold Ionization of Xenon by Chirped Intense Laser Pulses

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2014年第6期31卷 86-89页

作者：王传亮孙仁平陈永菊龚成赖炫扬康会鹏全威柳晓军 State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 University of Chinese Academy of Sciences Beijing 100090

We experimentally investigate above-threshold ionization of xenon subject to chirped intense laser pulses. While for few-cycle laser pulses free of chirp, the Freeman resonance narrow peaks in the photoelectron spectra become strongly suppressed, they will re-emerge for laser pulses with a certain chirp. Moreover, the position of the resonant peaks exhibits a strong dependence on the direction of the chirp. The experimental features can be understood by a two-step ionization process; that is, a multi-photon excitation plus subsequent ionization process.

关键词： IONIZATION (Atomic physics) IONIZATION energy XENON compounds MASS spectrometers NUCLEAR magnetic resonance spectroscopy physical & theoretical chemistry

Average Mean Escape Time for an Overdamped Spatially-Periodic System and Application to Josephson Junction ＊

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2014年第6期31卷 34-37页

作者：李静辉 Faculty of Science Ningbo University Ningbo 315211

We investigate the average mean escape time of particles over a potential barrier for an overdamped spatially periodic system driven by thermal fluctuations and subject to a dc constant bias force and an ac time-oscillatory drive. Some new anomalous behaviors of the average mean escape time are found, including： multiple reso- nant activation, multiple anti-Resonant activation, and thermally weakened stability. Some of the experimental verifications of these results are theoretically applied to the Josephson junction.

关键词： JOSEPHSON junctions MATHEMATICAL models FUNCTIONAL equations STOCHASTIC processes PROBABILITY theory physical & theoretical chemistry

A Simple Interconnection Layer for Tandem Organic Solar Cells with Improved Efficiency and Fill Factor

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2014年第6期31卷 246-249页

作者：郑克宁杨利营曹焕奇秦文静印寿根 Key Laboratory of Display Materials and Photoelectric Devices (Ministry of Education) and School of Materials Science and Engineering fianjin University of Technology Xianjin 300384 Tianjin Key Laboratory for Photoelectric Materials and Devices Tianjin 300384

We demonstrate a simple interconnection layer （ICL） that can be employed in tandem organic solar cells. An ICL with an optimized structure of Ca/Au/MoO3 is used between two sub cells composed of identical regioregularpoly（3-hexylthiophen）（P3HT）：[6,6]-phenyl C61-butyric acid methylester （PCBM） photoactive layers. Power conversion efficiency （PCE） of 3.24% and fill factor （FF） of 68.0% are achieved with such an ICL under simulated sunlight （1 O0 m W. cm- 2 ）. Compared with the best values of devices with ICLs of Ca/Al/MoOa, PCE is improved by 68.9% and FF is improved by 15.5%. The improved performances are attributed to the optical and electrical balances in both sub cells. The presented ICL extracts free charges efficiently from both sub cells thereby suppressing the exaction recombination in each sub cell.

关键词： PHOTOVOLTAIC cells SOLAR energy RENEWABLE energy sources SOLAR cells METHYLESTERASES physical & theoretical chemistry

Structure Dependence of Magnetic Properties for Annealed GaMnN Films Grown by MOCVD

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2014年第6期31卷 203-206页

作者：姜显哲杨学林纪骋邢海英杨志坚王存达于彤军张国义 State Key Laboratory of Artificial Microstructure and Mesoscopic Physics School of Physics Peking University Beijing 100871 School of Electronics and Information Engineering Tianjin Polytechnic University Tianjin 300387

GaMnN/GaN multilayers and conventional GaMnN single layers are grown by metal-organic chemical vapor deposition. Both kinds of samples show room-temperature ferromagnetism. After thermal annealing, the sample with GaMnN/GaN multilayer structure displays a larger coercivity and better thermal stability compared to the GaMnN single layer. The annealing effects on Vca related defects are observed from photoluminescenee measurements. Moreover, a different magnetic behavior is also found in the annealed GaMnN films grown on different （n-type GaN and p-type GaN） templates. These kinds of structure-dependent magnetic behaviors indicate that defects or carriers transformation introduced during annealing may have important effects on the electronic structure of Mn ions and on the ferromagnetism. Our work may be helpful for further understanding the origin of ferromagnetism in GaN-based diluted magnetic semiconductors.

关键词： SEMICONDUCTOR industry HIGH technology industries CONDENSED matter physics SUPERCONDUCTORS -- Magnetic properties physical & theoretical chemistry ANNEALING of metals

Effect of Mixing Assortativity on Extreme Events in Complex Networks

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2014年第6期31卷 250-254页

作者：凌翔 School of Transportation Engineering Hefei University of Technology Hefei 230009

We investigate the effect of mixing assortativity on the occurrence of extreme events in complex networks. The bias random walk model is adopted with a preferential transition probability tuned by a parameter We derive exact expressions for the stationary distribution probability and for the occurrence probability of extreme events. They reveal that the occurrence of extreme events strongly depends on the mixing assortativity of the network. It is shown that, for non-assortative （rk = 0）, assortative （rk = 0.15） and disassortative （rk = -0.15） scale-free networks, the minimal occurrence of extreme events will happen at α= -1.0, α = -0.6 ands = 0.2, respectively.

关键词： DISTRIBUTION (Probability theory) CHARACTERISTIC functions MATHEMATICAL analysis physical & theoretical chemistry FLUCTUATIONS (Physics) STOCHASTIC processes

Electromagnetic Transition Strengths and New Insight into the Chirality in ^106Ag

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2014年第6期31卷 59-62页

作者：郑云竺礼华吴晓光贺创业李广生郝昕于蓓蓓姚顺和张彪徐川王建国顾龙 China Institute of Atomic Energy Beijing 102413 School of Physics and Nuclear Energy Engineering Beihang University Beijing 100191 Faculty of Science Shenzhen University Shenzhen 518060 School of Physics Peking University Beijing 100871 Department of Physics Tsinghua University Beijing 100084

Excited states in ^106Ag are populated through the heavy-ion fusion evaporation reaction ^100Mo（ll B,5n）^106Ag at a beam energy of 60MeV. Lifetimes are measured for transitions of the two negative-parity rotational bands in the nucleus ^106Ag. The reduced transition probabilities show a great difference between the two bands. The staggering of the B（M1） and B（M1）/B（E2） values with spin are not observed. The bands are identified to be built on two distinct quasiparticle configurations. These results are contrary to an earlier suggestion that the pair of bands in ^106Ag are chiral doublet bands.

关键词： CORRELATION (Statistics) ELECTROMAGNETIC compatibility ELECTROMAGNETIC devices PARTICLES (Nuclear physics) -- Chirality QUASIPARTICLES (Physics) MATHEMATICAL analysis physical & theoretical chemistry