《大学物理》课程教学改革的几点思考
作者：
袁剑辉;厉江帆
期刊：
才智(才情斋) ,2018年(18):50 ISSN：1673-0208
作者机构：
长沙理工大学物理与电子科学学院;[厉江帆; 袁剑辉] 长沙理工大学
关键词：
大学物理;教学方法;改革
摘要：
针对当前理工院校开设的大学物理教学现状的进行了分析,就大学物理课堂教学内容、教学方法、练习方式及考核等方面的教学改革提出了几点建议,为促进大学物理教学在内容、方法、手段上进行改革、提高学生学习积极性,增强学生创新能力等方面提供参考。
语种：
中文
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Rectifying performance and negative differential behavior in graphite-chain-carbon nanotube junctions
作者：
Qiu, Ming;Li, Jiangfan;Liew, K. M.* ;Yuan, Chris
期刊：
Applied Physics Letters ,2014年104(2):023102 ISSN：0003-6951
通讯作者：
Liew, K. M.
作者机构：
[Yuan, Chris; Qiu, Ming] Univ Wisconsin, Dept Mech Engn, Milwaukee, WI 53211 USA.;[Li, Jiangfan; Qiu, Ming] Changsha Univ Sci & Technol, Sch Phys & Elect Sci, Changsha 410114, Hunan, Peoples R China.;[Liew, K. M.] City Univ Hong Kong, Dept Civil & Architectural Engn, Kowloon, Hong Kong, Peoples R China.
通讯机构：
[Liew, K. M.] C;City Univ Hong Kong, Dept Civil & Architectural Engn, Kowloon, Hong Kong, Peoples R China.
关键词：
ab initio calculations;carbon nanotubes;charge transfer states;density functional theory;electronic density of states;graphite;Green's function methods;infrared spectra;nanofabrication;negative resistance;rectification;visible spectra
摘要：
In this paper, the (5, 5) capped carbon nanotubes (CNTs) in contact with different lengths of sp monoatomic chains grown on the surface of graphite substrate are fabricated and its electronic transport properties sandwiched between CNT and graphite electrodes are investigated. The first-principles calculations based on nonequilibrium Green's function in combination with density-functional theory show that their rectifying performance and negative differential resistance behavior are observed under very low biases and obviously are enhanced when the length increases. From our analysis, the charge transfer, transmission spectra, projected density of states and evolutions of molecular orbitals are responsible for these phenomena. © 2014 AIP Publishing LLC.
语种：
英文
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Effects of Common Functional Groups on the Elastic Properties of Graphene Nanoribbons
作者：
Guo, Xu;Yuan, Jianhui* ;Li, Jiangfan
期刊：
Current Nanoscience ,2014年10(4):573-581 ISSN：1573-4137
通讯作者：
Yuan, Jianhui
作者机构：
[Guo, Xu; Yuan, Jianhui; Li, Jiangfan] Changsha Univ Sci & Technol, Sch Phys & Elect Sci, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[Yuan, Jianhui] C;Changsha Univ Sci & Technol, Sch Phys & Elect Sci, Changsha 410114, Hunan, Peoples R China.
关键词：
Chemical bond theory;elastic property;graphene;modification;molecular dynamics
摘要：
The elastic properties of armchair and zigzag graphene nanoribbons grafted with different functional groups are investigated using molecular dynamics. The simulation results show that the Young’s moduli of graphenes with autoupdate- grafted hydrogen (-H) are 982 GPa for zigzag and 1046 GPa for armchair. When the graphenes are grafted with hydroxyl (-OH), amine (–NH2), carboxylic (–COOH), and thiol (–SH) groups, Graphene–OH shows the highest Young’s modulus, followed by graphene–COOH. Among the moduli obtained, those for graphene–NH2 and graphene–SH, which are nearly identical to that of graphene–H, are the lowest. The modulus variations of the zigzag and armchair graphenes with different grafts have similar trends, but the moduli for armchair graphenes are always higher than those for zigzag graphenes. This phenomenon is analyzed on the basis of the radial distribution function, deformation electron density, and chemical bond theory. The results indicate that smaller oxygen-containing functional groups, as well as the C–O or C–C–O bond formations caused by grafted atoms with dangling bonds, could effectively enhance the flexibility of the graphenes while maintaining their stability. The elastic performance of the grafted armchair graphenes is superior to that of the grafted zigzag graphenes. © 2014 Bentham Science Publishers.
语种：
英文
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Classical correlation, quantum discord and entanglement for two-qubit system subject to heat bath
作者：
Wang, Chengzhi* ;Li, Chunxian;Nie, Liuying;Li, Xiufeng;Li, Jiangfan
期刊：
Optics Communications ,2011年284(9):2393-2401 ISSN：0030-4018
通讯作者：
Wang, Chengzhi
作者机构：
[Wang, Chengzhi; Li, Xiufeng; Li, Chunxian; Li, Jiangfan; Nie, Liuying] Changsha Univ Sci & Technol, Dept Phys & Elect Sci, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[Wang, Chengzhi] C;Changsha Univ Sci & Technol, Dept Phys & Elect Sci, Changsha 410114, Hunan, Peoples R China.
关键词：
Classical correlation;Decoherence;Decoherence models;Entanglement;Heat bath;Initial state;Quantum discord;Sudden change;Sudden deaths;Two-qubit system;Correlation methods;Electrostatic devices;Electrostatic discharge;Quantum entanglement
摘要：
Classical correlation (CC), quantum discord (QD) and entanglement (QE) of two qubits in one-side and two-side decoherence models are investigated. The sudden change of quantum discord (DSC) as well as classical correlation and sudden death of entanglement (ESD) are found. It is proved that QE (QD) presents no sudden change (sudden death). We prove that, for nonzero occupation number of the reservoir, QE must suffer sudden death; For zero occupation number and X-form initial states, we obtain the states which are robust and the states which experience sudden death. It is verified that if DSC and ESD occur under one-side decoherence, then it must appear in the two-side decoherence, while the reverse does not hold. We obtain the boundaries of CC-QE plane and QD-QE plane, and give the state possessing maximal amount of CC (QD) for a given amount of QE. © 2010 Elsevier B.V. All rights reserved.
语种：
英文
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Classical correlation and quantum discord mediated by cavity in two coupled qubits
作者：
Wang, Cheng-Zhi* ;Li, Chun-Xian;Nie, Liu-Ying;Li, Jiang-Fan
期刊：
Journal of Physics B: Atomic, Molecular and Optical Physics ,2011年44(1):015503 ISSN：0953-4075
通讯作者：
Wang, Cheng-Zhi
作者机构：
[Li, Jiang-Fan; Li, Chun-Xian; Wang, Cheng-Zhi; Nie, Liu-Ying] Changsha Univ Sci & Technol, Dept Phys & Elect Sci, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[Wang, Cheng-Zhi] C;Changsha Univ Sci & Technol, Dept Phys & Elect Sci, Changsha 410114, Hunan, Peoples R China.
关键词：
Classical correlation;Coupled qubits;In-vacuum;Qubit coupling;Sudden change;Thermal equilibrium state;Two-level atom;Vacuum state;Atoms;Behavioral research;Photons;Superconducting materials;Thermodynamics;Vacuum;Quantum entanglement
摘要：
We study the dynamics of classical correlation and quantum discord of two coupled two-level atoms interacting with a cavity initially in vacuum, coherent and thermal equilibrium states, respectively. The interplay between the atom-atom coupling and mean number of photons is considered. We find that, for a cavity in a vacuum state, classical correlation or quantum discord shows a sudden change in behaviour during the evolution, and evolves periodically for zero and very large qubit-qubit couplings. However, for coherent and thermal equilibrium states, the classical correlation and quantum discord present the phenomenon of collapse-revival when the qubit-qubit coupling is much greater than the mean number of photons. The period of collapse-revival becomes long as the qubit-qubit coupling and mean number of photons increase. The relationship between quantum discord and entanglement in the studied system is considered. © 2011 IOP Publishing Ltd.
语种：
英文
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Time evolution, squeezing and entanglement for an optical frequency up-conversion with a driving term
作者：
Li, Jiang-Fan* ;Liu, Shi-Fa;Wang, Cheng-Zhi;Li, Xiu-Feng;Fang, Jia-Yuan
期刊：
Journal of Modern Optics ,2011年58(1):52-61 ISSN：0950-0340
通讯作者：
Li, Jiang-Fan
作者机构：
[Liu, Shi-Fa; Li, Jiang-Fan; Wang, Cheng-Zhi; Fang, Jia-Yuan; Li, Xiu-Feng] Changsha Univ Sci & Technol, Sch Phys & Elect Sci, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[Li, Jiang-Fan] C;Changsha Univ Sci & Technol, Sch Phys & Elect Sci, Changsha 410114, Hunan, Peoples R China.
关键词：
Entanglement;Frequency up-conversion;Lewis-Riesenfeld invariant theory;Squeezing;Time evolution
摘要：
By using the Lewis-Riesenfeld quantum invariant theory, an explicit analytical solution for the time evolution operator of the frequency up-conversion system with a driving term is obtained. It is then used to investigate mainly the influence of the driving term, frequency detuning, and the initial states on the quantum statistical properties of the output-coupled fields. It is found that the time evolution for the general up-conversion system can efficiently convert a low-frequency squeezed light into a high-frequency squeezed light, in the case of zero-detuning, but the squeezed effect of the output fields is independent of the driving term. It is also shown that there is an entanglement between the signal and idler output photons for the general up-conversion system. ©2011 Taylor &Francis.
语种：
英文
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Entanglement death and teleportation pre-emption in a dissipative system of two coupled qubits
作者：
Li, Chun-Xian* ;Wang, Cheng-Zhi;Nie, Liu-Ying;Li, Jiang-Fan
期刊：
Optics Communications ,2010年283(10):2294-2300 ISSN：0030-4018
通讯作者：
Li, Chun-Xian
作者机构：
[Li, Jiang-Fan; Li, Chun-Xian; Wang, Cheng-Zhi; Nie, Liu-Ying] Changsha Univ Sci & Technol, Dept Phys & Elect Sci, Changsha 410114, Hunan, Peoples R China.
通讯机构：
[Li, Chun-Xian] C;Changsha Univ Sci & Technol, Dept Phys & Elect Sci, Changsha 410114, Hunan, Peoples R China.
关键词：
Bloch sphere;Coupled qubits;Coupling strengths;Dissipative systems;Entanglement decays;Entanglement sudden death;Measurement results;Multimodes;Squeezed vacuum fields;Squeezing parameter;Teleportation protocol;Electrostatic devices;Electrostatic discharge;Vacuum
摘要：
We discuss the entanglement of two coupled qubits each of which is interacting with a multi-mode squeezed vacuum field reservoir and the possibility to use them in a teleportation protocol. The entanglement sudden death (ESD) and teleportation pre-emption (TPE) are discovered in this system. We consider the interplay between the coupling strength and the squeezing parameter, and find that they play competing roles in entanglement as well as in teleportation. We show in detail how the entanglement decay affects the teleportation. It is interesting to show that TPE precedes ESD in general, and for given measurement result and squeeze parameter all output states of teleportation for a long time arrive at a fixed asymptotic point in the Bloch sphere. © 2010 Elsevier B.V. All rights reserved.
语种：
英文
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Time Evolution and Squeezing of Degenerate and Non-degenerate Coupled Parametric Down-Conversion with Driving Term
作者：
Li Jiang-Fan* ;Fang Jia-Yuan;Xiao Fu-Liang;Liu Xin-Hai;Wang Cheng-Zhi
期刊：
Communications in Theoretical Physics ,2009年51(3):514-518 ISSN：0253-6102
通讯作者：
Li Jiang-Fan
作者机构：
[Li Jiang-Fan; Wang Cheng-Zhi; Fang Jia-Yuan; Xiao Fu-Liang; Liu Xin-Hai] Changsha Univ Sci & Technol, Sch Phys & Elect Sci, Changsha 410076, Hunan, Peoples R China.
通讯机构：
[Li Jiang-Fan] C;Changsha Univ Sci & Technol, Sch Phys & Elect Sci, Changsha 410076, Hunan, Peoples R China.
关键词：
coupled parametric down-conversion;time evolution;Lewis-Riesenfeld invariant theory;Schrodinger equation;squeezed states
摘要：
By properly selecting the time-dependent unitary transformation for the linear combination of the number operators, we construct a time-dependent invariant and derive the corresponding auxiliary equations for the degenerate and non-degenerate coupled parametric down-conversion system with driving term. By means of this invariant and the Lewis-Riesenfeld quantum invariant theory, we obtain closed formulae of the quantum state and the evolution operator of the system. We show that the time evolution of the quantum system directly leads to production of various generalized one- and two-mode combination squeezed states, and the squeezed effect is independent of the driving term of the Hamiltonian. In some special cases, the current solution can reduce to the results of the previous works. © 2009 Chinese Physical Society and IOP Publishing Ltd.
语种：
英文
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Simulating Entangling Unitary Operator Using Non-maximally Entangled States
作者：
Li Chun-Xian* ;Wang Cheng-Zhi;Nie Liu-Ying;Li Jiang-Fan
期刊：
中国物理快报：英文版 ,2009年26(2):17-20 ISSN：0256-307X
通讯作者：
Li Chun-Xian
作者机构：
[Li Jiang-Fan; Wang Cheng-Zhi; Li Chun-Xian; Nie Liu-Ying] Changsha Univ Sci & Technol, Dept Phys & Elect Sci, Changsha 410004, Hunan, Peoples R China.
通讯机构：
[Li Chun-Xian] C;Changsha Univ Sci & Technol, Dept Phys & Elect Sci, Changsha 410004, Hunan, Peoples R China.
关键词：
No English Keywords
摘要：
We use non-maximally entangled states (NMESs) to simulate an entangling unitary operator (EUO) with a certain probability. Given entanglement resources, the probability of the success we achieve is a decreasing function of the parameters of the EUO. Given an EUO, for certain entanglement resources the result is optimal, i.e., the probability obtains a maximal value, and for optimal result higher parameters of the EUO match more amount of entanglement resources. The probability of the success we achieve is higher than the known results under some condition.
语种：
英文
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Entanglements induced by cavity interacting with two-coupled atoms
作者：
Wang, Cheng-Zhi* ;Li, Chun-Xian;Li, Jiang-Fan
期刊：
Optics Communications ,2009年282(6):1160-1166 ISSN：0030-4018
通讯作者：
Wang, Cheng-Zhi
作者机构：
[Li, Jiang-Fan; Li, Chun-Xian; Wang, Cheng-Zhi] Changsha Univ Sci & Technol, Dept Phys & Elect Sci, Changsha 410004, Hunan, Peoples R China.;[Wang, Cheng-Zhi] Changsha Univ Sci & Technol, Dept Phys & Elect Sci, Wan Jia Li Rd, Changsha 410004, Hunan, Peoples R China.
通讯机构：
[Wang, Cheng-Zhi] C;Changsha Univ Sci & Technol, Dept Phys & Elect Sci, Wan Jia Li Rd, Changsha 410004, Hunan, Peoples R China.
关键词：
Atomic physics;Light;Mixtures;Photons;Quantum optics;Quantum theory;Concurrence;Entanglement;Entanglement collapse and revival;Initial conditions;Numerica l results;Tavis-Cummings model;Atoms
摘要：
We consider a quantum optics model where the cavity interacts with two-coupled atoms. The atom-atom entanglement, atoms-cavity entanglement and the mixture for the two atoms are investigated, and discuss the effects of the initial conditions, atom-atom coupling and the mean number of photons on the entanglements and mixture. We find that atom-atom coupling plays an important role in the entanglement and mixture. Numerical results show that under some conditions the phenomena of "entanglement sudden death" and "entanglement collapse and revival" emerge. ©2008 Elsevier B.V. All rights reserved.
语种：
英文
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Effect of Chorus Latitudinal Distribution on Evolution of Outer Radiation Belt Electrons
作者：
Xiao Fuliang* ;Li Junqiu;Tang Lijun;He Yihua;Li Jiangfan
期刊：
等离子体科学与技术：英文版 ,2009年11(5):544-549 ISSN：1009-0630
通讯作者：
Xiao Fuliang
作者机构：
[Li Junqiu; Li Jiangfan; Tang Lijun; He Yihua; Xiao Fuliang] Changsha Univ Sci & Technol, Sch Phys & Elect Sci, Changsha 410004, Hunan, Peoples R China.;[Xiao Fuliang] Chinese Acad Sci, State Key Lab Space Weather, Beijing 100190, Peoples R China.
通讯机构：
[Xiao Fuliang] C;Changsha Univ Sci & Technol, Sch Phys & Elect Sci, Changsha 410004, Hunan, Peoples R China.
关键词：
wave-particle interaction;acceleration of energetic electrons;whistler-mode chorus;latitudinal distribution
摘要：
Primary result on the impact of the latitudinal distribution of whistler-mode chorus upon temporal evolution of the phase space density (PSD) of outer radiation belt energetic electrons was presented. We evaluate diffusion rates in pitch angle and momentum due to a band of chorus frequency distributed at a standard Gaussian spectrum, and solve a 2-D bounce-averaged momentum-pitch-angle Fokker-Planck equation at L = 4.5. It is shown that chorus is effective in accelerating electrons and can increase PSD for energy of similar to 1 MeV by a factor of 10 or more in about one day, which is consistent with observation. Moreover, the latitudinal distribution of chorus has a great impact on the acceleration of electrons. As the latitudinal distribution increases, the efficient acceleration region extends from higher pitch angles to lower pitch angles, and even covers the entire pitch angle region when chorus power reaches the maximum latitude lambda(m) = 45 degrees.
语种：
英文
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行星齿轮传动中内啮合中心轮齿圈径向共振问题的研究
作者：
黄劲枝;厉江帆
期刊：
湖南师范大学自然科学学报 ,2008年31(2):64-67+90 ISSN：2096-5281
作者机构：
顺德职业技术学院机电工程系,中国佛山,528300;长沙理工大学物理与电子科学学院,中国长沙,410073;[厉江帆] 长沙理工大学;[黄劲枝] 顺德职业技术学院
关键词：
行星齿轮传动;内齿圈;径向受迫振动;共振
摘要：
针对几种常用的行星齿轮传动类型,建立了内啮合中心轮齿圈的动力学微分方程,运用机械振动理论研究了其径向受迫振动情况.研究结果表明:2K-H型NGW、2K-H型NW和3K型NGWN传动装置的齿圈径向共振极难发生;而2K-H型NN传动装置的内齿圈径向共振容易发生.
语种：
中文
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Energetic particles modeled by a generalized relativistic kappa-type distribution function in plasmas
作者：
Xiao, Fuliang* ;Chen, Liangxu;Li, Jiangfan
期刊：
Plasma Physics and Controlled Fusion ,2008年50(10):105002 ISSN：0741-3335
通讯作者：
Xiao, Fuliang
作者机构：
[Chen, Liangxu; Xiao, Fuliang; Li, Jiangfan] Changsha Univ Sci & Technol, Sch Phys & Elect Sci, Changsha 410076, Hunan, Peoples R China.;[Xiao, Fuliang] State Key Lab Space Weather, Beijing 100080, Peoples R China.
通讯机构：
[Xiao, Fuliang] C;Changsha Univ Sci & Technol, Sch Phys & Elect Sci, Changsha 410076, Hunan, Peoples R China.
摘要：
Energetic particles found in planetary magnetospheres and other plasmas often display a power law and an anisotropy (including loss cone and temperature anisotropy). In a recent study, a full relativistic kappa-loss cone (KLC) distribution f<sup>κL</sup> is initially introduced to model energetic particles, but f<sup>κL</sup> is only associated with loss cone anisotropy. We extend this previous study and develop a generalized relativistic kappa-type (KT) distribution f<sup>κT</sup> which incorporates either temperature anisotropy or both loss cone and temperature anisotropy. We carry out numerical calculations for a direct comparison between the new KT distribution, the previous KLC distribution and the kappa distribution f <sup>κ</sup>, respectively. We find that (a) analogous to f <sup>κL</sup>, f<sup>κT</sup> satisfies the power law not only at lower energies but also at relativistic energies;(b) analogous to f <sup>κ</sup>, f<sup>κT</sup> contains either temperature anisotropy or both loss cone and temperature anisotropy;(c) the regular kappa distribution is found to decrease faster than the KT distribution with kinetic energy E <inf>k</inf> especially when <sup>2</sup> increases (where <sup>2</sup> is the thermal characteristic parameter), e.g. f<sup>κ</sup>/f<sup>κT</sup> ≲10<sup>-2</sup> for E<inf>k</inf> ≳2.0 MeV and <sup>2</sup> ≳0.3;(d) no big difference occurs between both KT and kappa distributions through energies up to ∼500 keV for <sup>2</sup> ≲0.03 and (e) the three distributions show different anisotropy behaviors even for the same overall anisotropy. The results suggest that the new generalized KT distribution may be applied in space plasmas and other plasmas including laboratory machines where highly energetic particles exist. ©2008 IOP Publishing Ltd.
语种：
英文
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Characteristics of Wave--Particle Interaction in a Hydrogen Plasma
作者：
He Hui-Yong* ;Chen Liang-Xu;Li Jiang-Fan
期刊：
中国物理快报：英文版 ,2008年25(9):3511-3514 ISSN：0256-307X
通讯作者：
He Hui-Yong
作者机构：
[Li Jiang-Fan; Chen Liang-Xu; He Hui-Yong] Changsha Univ Sci & Technol, Sch Phys & Elect Sci, Changsha 410076, Hunan, Peoples R China.;[He Hui-Yong] State Key Lab Space Weather, Beijing 100080, Peoples R China.
通讯机构：
[He Hui-Yong] C;Changsha Univ Sci & Technol, Sch Phys & Elect Sci, Changsha 410076, Hunan, Peoples R China.
关键词：
cyclotron wave;plasma;hydrogen plasma;calculations;energy;wave frequency
摘要：
We study the characteristics of cyclotron wave–particle interaction in a typical hydrogen plasma. The numerical calculations of minimum resonant energy -Emin, resonant wave frequency ω, and pitch angle diffusion coefficient Dαα for interactions between R-mode/L-mode and electrons/protons are presented. It is found that -Bmin decreases with ω for R-mode/electron, L-modefproton and L-mode/electron interactions, but increase with ω for R-mode/proton interaction. It is shown that both R-mode and L-mode waves can efficiently scatter energetic (10keV~100keV) electrons and protons and cause precipitation loss at L = 4, indicating that perhaps wave–particle interaction is a serious candidate for the ring current decay.
语种：
英文
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非简并参量下转换系统两个不同形式解间的关系
作者：
厉江帆;姜宗福;单树民
期刊：
湖南师范大学自然科学学报 ,2007年30(04):40-45 ISSN：2096-5281
作者机构：
长沙理工大学物理与电子科学学院,中国,长沙,410076;国防科技大学理学院,中国,长沙,410073;[厉江帆; 单树民] 中国人民解放军国防科技大学;[姜宗福] 长沙理工大学
关键词：
Lewis-Riesenfeld不变量理论;非简并参量下转换;纠缠态表象;解析解
摘要：
进一步研究了我们在前一篇论文中采用Lewis-Riesenfeld不变量理论和采用纠缠态表象所求得的非简并光学参量下转换系统薛定谔方程两个解间的关系.发现我们所求得的在k2>1,k2=1,k2<1和k=0时的解析表达式,分别对应于非简并参量下转换系统在域值以上、域值、域值以下以及参量共振情形的解;当k=-1时,此解与范等的结果完全一致,而范氏解实际上相应于频率简并但偏振非简并的失谐参量下转换系统的域值解;还对在特殊情况下如何从此解析解过渡到范氏解进行了详细的推导.
语种：
中文
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An explicit analytical solution of the Schrodinger equation for a detuned quantum frequency conversion system
作者：
Li Jiang-Fan* ;Shan Shu-Min;Yang Jian-Kun;Jiang Zong-Fu
期刊：
物理学报 ,2007年56(10):5597-5601 ISSN：1000-3290
通讯作者：
Li Jiang-Fan
作者机构：
[Li Jiang-Fan] Changsha Univ Sci & Technol, Inst Phys & Elect Sci, Changsha 410076, Peoples R China.;Changsha Univ Sci & Technol, Inst Comp & Telecommun Engn, Changsha 410076, Peoples R China.;Natl Univ Def Technol, Inst Sci, Changsha 410073, Peoples R China.
通讯机构：
[Li Jiang-Fan] C;Changsha Univ Sci & Technol, Inst Phys & Elect Sci, Changsha 410076, Peoples R China.
关键词：
量子频率转换;薛定谔方程;解析解;Lewis-Riesenfeld不变量方法
摘要：
根据光和频产生过程的动力学演化总是保持闲置光和信号光的光子数之和守恒这一性质,构建出了光学谐振腔中频率转换系统的含时不变量.并运用此不变量及Lewis-Riesenfeld量子不变量方法,在失谐情形下,对这一双模量子化电磁场耦合系统相应的薛定谔方程进行了求解.得到了系统随时间演化的量子态和演化算符的显示解析表达式.此解对于进一步研究系统各种量子性质是有用的.
语种：
中文
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克尔介质中压缩真空场与耦合双原子依赖强度耦合系统光场的压缩特性
作者：
方家元;厉江帆;黄春佳;黄祖洪
期刊：
光学学报 ,2006年26(6):921-927 ISSN：0253-2239
通讯作者：
Fang, J.(fangjy@csust.edu.cn)
作者机构：
[方家元; 黄春佳; 厉江帆; 黄祖洪] Department of Physics and Electronic Science, Changsha University of Science and Technology, Changsha 410077, China;[方家元; 黄春佳; 厉江帆; 黄祖洪] Institute of Optoelectronics, Changsha University of Science and Technology, Changsha 410077, China
通讯机构：
[Fang, J.] D;Department of Physics and Electronic Science, , Changsha 410077, China
关键词：
量子光学;克尔介质;非共振相互作用;依赖强度耦合;光场的正交压缩
摘要：
研究了存在克尔介质时依赖强度耦合单模压缩真空场与耦合双原子非共振相互作用系统光场的压缩性质，运用数值方法讨论了系统参量对光场压缩性质的影响。结果表明：克尔介质、失谐量、原子间相互作用、光场初始压缩因子对光场的压缩性质有较大的影响。随原子间偶极-偶极相互作用的增大，光场的压缩随时间逐渐变浅，压缩的次数减少；随克尔效应或失谐量的增大，光场的压缩程度先逐渐变浅后增强、压缩次数先减少后增多；当光场初始压缩因子较小时，光场压缩程度较小，当光场初始压缩因子较大时，光场压缩程度增大；而原子的初始状态对光场的压缩程度没有明显的影响。
语种：
中文
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A general solution for the dynamics of a generalized non-degenerate optical parametric down-conversion interaction by virtue of the Lewis-Riesenfeld invariant theory
作者：
Li, JF* ;Jiang, ZF;Xiao, FL;Huang, CJ
期刊：
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL ,2005年38(20):4459-4468 ISSN：1751-8113
通讯作者：
Li, JF
作者机构：
[Li, JF] Changsha Univ Sci & Technol, Dept Phys & Elect Sci, Hunan 410077, Peoples R China.;Natl Univ Def Technol, Inst Sci, Changsha 410073, Peoples R China.
通讯机构：
[Li, JF] C;Changsha Univ Sci & Technol, Dept Phys & Elect Sci, Hunan 410077, Peoples R China.
摘要：
The dynamics of a generalized non-degenerate optical parametric down-conversion interaction whose Hamiltonian includes an arbitrary time-dependent driving part and a two-mode coupled part is studied by adopting the Lewis-Riesenfeld invariant theory. The closed formulae for the evolution of the quantum states and the evolution operators of the system are obtained. It is shown that various generalized squeezed states arise naturally in the process, and the two-mode squeezed effect is independent of the driving part. An explicitly analytical solution of the Schrödinger equation is further derived as the classical generalized force acting on each mode and the coupling of the two modes both have harmonic time dependences. This solution is found to be in agreement with previous research in special cases. © 2005 IOP Publishing Ltd.
语种：
英文
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The time evolution and the quantum fluctuation for two forced quantum oscillators with mixing of two modes
作者：
Li, JF* ;Xiao, FL;Jiang, ZF;Fang, JY
期刊：
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL ,2005年38(42):9297-9307 ISSN：1751-8113
通讯作者：
Li, JF
作者机构：
[Li, JF] Changsha Univ Sci & Technol, Dept Phys & Elect Sci, Hunan 410077, Peoples R China.;Natl Univ Defense Technol, Inst Sci, Hunan 410073, Peoples R China.
通讯机构：
[Li, JF] C;Changsha Univ Sci & Technol, Dept Phys & Elect Sci, Hunan 410077, Peoples R China.
摘要：
By using the Lewis-Riesenfeld quantum invariant theory and properly choosing Hermitian invariant operator, a closed solution of the Schrödinger equation is derived for two forced quantum oscillators with mixing of two modes, and the quantum fluctuations in the output fields are evaluated. For the initial two-mode squeezed number or squeezed coherent state, in some particular conditions, the time evolution of the oscillators can not only preserve the initial two-mode squeezing, but also produce squeezing in the individual modes; and exhibit a periodical squeezing behaviour. For the initial two-mode number state or coherent state, there is no squeezing in the individual and mutual quadrature phases of the two-mode fields. Furthermore, regardless of which state above being initially considered, the quantum fluctuations of all the quadrature phases in the output fields are all independent of the driving parameters. In particular, for the initial two-mode coherent state, the variances of the output fields are also independent of other parameters in the Hamiltonian, and always preserve their initial values 1/4. © 2005 IOP Publishing Ltd.
语种：
英文
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依赖强度耦合双光子T-C模型原子布居数的时间演化
作者：
方家元;黄春佳;肖伏良;厉江帆
期刊：
长沙理工大学学报(自然科学版) ,2005年2(3):79-84 ISSN：1672-9331
作者机构：
长沙理工大学,物理与电子科学系,湖南,长沙,410076;长沙理工大学,光电子学研究所,湖南,长沙,410076;[厉江帆; 方家元; 黄春佳; 肖伏良] 长沙理工大学
关键词：
压缩真空场;耦合双原子;依赖强度耦合;原子布居
摘要：
研究了依赖强度耦合压缩真空场与耦合双原子双光子跃迁相互作用系统原子布居数的时间演化规律,讨论了光场的初始压缩因子、原子间相互作用和原子的初态对原子布居数时间演化的影响.结果表明:当原子间相互作用较弱时,原子布居的时间演化曲线呈现周期性的崩塌-回复现象,随着原子间相互作用的加强,崩塌-回复周期变短,以至消失.原子布居时间演化曲线的振荡幅度随光场初始压缩因子的增大而明显地减小.
语种：
中文
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