【作者】 郑军；

【导师】 刘正东；

【作者基本信息】 南昌大学 ， 材料物理与化学， 2009， 博士

【摘要】 本论文对量子干涉现象进行了系统的理论研究。量子干涉是激光物理和量子光学的重要前沿课题。近来研究已经发现诸如相干布居俘获,电磁感应透明,无吸收折射率增强,电磁感应左手效应等量子干涉效应。这些研究有潜在的应用价值,如能够控制介质相干性质,产生高频激光,信息存贮和高精密测量等等。本论文根据内容分为八个部分:第1章介绍研究背景和主要研究内容,第2章是研究光与物质相互作用的半经典理论的回顾,其余六个部分介绍作者的主要工作。第3章运用数值模拟的方法讨论了M型五能级原子与外场相互作用系统对探测场的吸收和色散等光学性质。发现改变控制场拉比频率时,系统的吸收和色散性质会发生规律性变化。在特定区域会呈现出EIT,当拉比频率减小时,EIT窗口变窄并且介质色散增强可获得慢光速光脉冲。第4章研究双∧型结构原子与四个光场相互作用的量子系统,探讨双驱动场下,系统量子效应如何通过双驱动场的配合来实现调控。第5章阐述了多能级系统中的Vacuum-Induced Coherence(VIC)效应是一种重要的量子干涉效应,并且研究发现VIC效应会使系统产生电磁感应透明现象、改变系统的吸收、增益和色散等性质,分析在VIC效应的条件下系统能级粒子数分布的动力学行为。另外,考虑复数拉比频率的相位变化时系统呈现出光学双稳态效应。第6章采用数值模拟方法,首先研究倒Y型四能级原子与三个光场相互作用系统对探测光的吸收和色散性质,然后研究了介质的相对介电常数和相对磁导率受电磁诱导发生显著变化,在合适的参数条件下它们同时出现负值,产生了左手效应,相应的介质转化为左手材料。随着系统参数的改变,左手效应频率范围等性质随之变化。第7章研究了具有超精细结构的四能级原子系统在电磁感应下的左手效应,讨论了由交叉耦合自发辐射路径引起的真空诱导相干对左手效应的影响。研究表明,真空诱导相干效应的强弱对介质的相对介电常数和相对磁导率实部负值的取值范围有显著影响,介质的左手效应随VIC效应的增大而增强。第8章研究了V型四能级原子系统在电磁诱导下的左手效应,结果显示系统不仅在弱探测场强耦合场情况下出现左手效应,还在探测光场与耦合光场相同数量级的条件下呈现出左手效应,增加探测场还使得负折射率取值范围增加,增强了左手效应。最后一章给出全文总结。更多还原

【Abstract】 The thesis focused on the systematically theoretical study on some phenomena about atomic coherence and quantum interference. Quantum coherence and interference has become one of the important forward subjects in laser physics and quantum optics. Recent studies have shown a lot of quantum phenomena such as coherent population trapping, electromagnetically induced transparency, index enhancement without absorption, electromagnetically induced handedness, etc. These new effects have great potential for the control of the coherence properties of a medium, the production of high frequency lasers, the information storage and high precision measurements.This thesis is presented as eight sections according to the contents: Chapter 1 is an introduction of the research background and the research purpose of the thesis. Chapter 2 is a review on the semi-classical theory of light-matter interaction. The following six sections are the introductions of the author’s work.In Chapter 3, the absorption-dispersion properties in a M- type five-level atomic system interacting with external fields system have been discussed. It is shown that changing the control fields can influence the absorption-dispersion properties regularly. The electromagnetically induced transparency (EIT) can be obtained if the parameters are taken appropriately. When control fields Rabi frequencies were decreased, the EIT windows would be narrow and slow-light would be realized.In Chapter 4, the quantum mechanics system of interacting between double∧type four-lever atoms and four light fields is studied, we investigates how to realize quantum effect manipulation under double cooperating drive light fields.In chapter 5, we report the effects of Vacuum-Induced Coherence in a laser-driven four-level atom consisting of three near-degenerate upper levels have an additional coherence term due to interaction with the vacuum of the radiation field. We show that such coherence preserves electromagnetically induced transparency and optical bi-stability phenomena. The dynamical behaviors of the population distribution via vacuum-Induced coherence was analyzed numerically too.In chapter 6, the system of inverted Y-type four-level atoms interacted with multi-mode light fields is investigated. Firstly, the absorption-dispersion properties of the medium are discussed. Then the left handedness of the medium under the mechanism of quantum interference is discussed.In chapter 7, the electromagnetically inductive left-handedness in a four-level atomic system associated with a pair of upper excited hyperfine levels has been investigated. We also discussed the properties of left-handedness with vacuum-induced coherence arising from the cross coupling spontaneous emission pathways.In chapter 8, a V-type four-level atomic system has been investigated for realizing left handedness. It is shown that the negative refractive index can be achieved not only in the condition of weaker probe field and stronger coupling field, but also in the condition which the probe field and the coupling field are in the same order. The negative refractive index band is enlarged in the situation of stronger probe field and left handedness is enhanced.At last, the summary of the paper is presented.This project is supported by the National Natural Science Foundation of China (Grant No. 10464002, No. 60278016, No.60768001)更多还原