Tavis-Cummings模型中的量子态平均保真度

运用全量子理论,研究了Tavis-Cummings模型中量子态平均保真度的演化特性,对原子和光场的初态以及两原子的关联程度对平均保真度的影响进行了研究.结果表明,原子、光场和系统的平均保真度依赖于初态时2个原子处在基态的几率以及光场处于真空态的几率;初态两原子在基态无关联,光场处于真空态,体系不失真.     

激发相干态与级联三能级原子的量子信息保真度

讨论了激发相干态光场与级联三能级原子相互作用时原子、光场和整个系统的量子信息保真度的时间演化过程。研究了光场参数和失谐量对保真度的影响。结果表明,光场参数和失谐量对保真度的振荡频率和振荡周期有明显影响,而对保真度的平均值影响甚微。     

单模真空场-耦合双原子系统的量子保真度演化

本文利用全量子理论,研究了单模真空场-耦合双原子系统的量子保真度演化特性。结果表明,原子与原子之间偶极相互作用的耦合系数、原子与光场之间的耦合系数以及初态时两个原子均处于基态的几率等因素影响着保真度的演化规律。当原子与原子之间偶极相互作用增大时,整个体系的保真度增大,并且演化曲线出现崩溃-回复特征;当原子和光场之间的耦合系数增大时,整个体系的保真度减小,并且演化曲线的周期明显变小;当初态两原子均处在基态的概率增大时,整个体系的保真度增大。     

耗散腔场中双纠缠原子的量子信息保真度

利用数值计算的方法,研究了耗散腔中双纠缠原子的量子信息保真度.讨论了光场的初始平均光子数一定的情况下腔的耗散系数对量子态保真度的影响,以及在腔的耗散一定的情况下光场的初始平均光子数对量子态保真度的影响.结果表明:腔的耗散和光场的初始平均光子数对原子和原子—光场系统的保真度的影响都很明显.     

热光场与运动二能级原子相互作用系统的保真度

借助于数值计算方法,研究了热光场与运动二能级原子相互作用系统的保真度,讨论了原子的初始状态、运动速度及光场的初始平均光子数对系统保真度的影响.结果表明原子初始状态、运动速度及光场的初始平均光子数都对保真度有不同程度的影响.     

场频率变化对保真度的影响

利用数值计算、数学推导,对比研究等方法,研究了场频率作正弦微小变化时原子与光场相互作用系统中保真度的演化.研究表明:场频率变化的幅值越大,即失谐量越大,则系统、光场和原子的保真度就越大;另外,场频率变化的角频率只影响系统、光场和原子的保真度演化曲线变化频率,当场频率变化的角频率增大一倍,则演化曲线的频率也增大一倍.     

数态光场与2原子相互作用系统保真度的调控

利用数值计算的方法研究了数态光场与初始处于激发态的2个两能级原子相互作用系统的保真度,讨论了光场的失谐量、光场的光子数和对原子操作后对系统保真度的影响.结果表明,不对原子进行操作,初始时刻信息完全不失真,并且可以通过控制场和原子的失谐量和光场的光子数来操控系统保真度的振荡频率、峰值和周期性;对原子进行操作,初始时刻信息就出现失真现象,而且可以通过操作经典场来实现对系统保真度的调控.     

与纠缠原子作用的二项式光场的量子信息保真度

应用全量子理论研究了初始处于纠缠态双原子与二项式光场共振相互作用的光场量子信息保真度.采用数值计算方法,讨论了原子纠缠度、二项式光场参量和相互作用时间对保真度的影响.结果表明:选取恰当的初始原子纠缠参量和初始二项式光场参量,以及控制好相互作用时间,可以获得光场的高保真输出.     

原子与双光场耦合系统量子信息保真度研究

讨论了在相位阻尼作用下，一个二能级原子与两个不同光场相互作用时系统的量子信息保真度随时间演化的过程，并对一个任意纯态量子比特通过光场与二能级原子耦合系统进行量子传输的保真度进行了研究，分析了系统作为传输信道对信息的支持程度（即系统的传真度）；着重讨论了相位阻尼和失谐对量子传输保真度的影响，并且获得了通过该信道进行传输的最大保真度。     

二项式光场和原子相互作用模型中的保真度

运用全量子理论对二项式光场和二能级原子相互作用模型中保真度的演化特性进行了研究，发现二项式光场的初始光子数和失谐量对保真度有明显的影响．结果表明，初始时刻二项式光场的平均光子数越大，保真度就越小；失谐量越大，保真度就越大．     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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