Δ-型三能级系统中的Fano类反对称共振的研究

项目名称： Δ-型三能级系统中的Fano类反对称共振的研究

项目编号： No.11464010

项目类型： 地区科学基金项目

立项/批准年度： 2015

项目学科： 数理科学和化学

项目作者： 何永林

作者单位： 河西学院

项目金额： 46万元

中文摘要： 手性分子、超导人工原子等对称性破缺系统中存在不同于基本构型Λ型、V型和Ξ型的Δ型三能级系统。2012年，申请人发现强静电场中的高激发态原子系统中也存在Δ型三能级系统。理论和实验研究表明，在对称性破缺的Δ型三能级系统中给定的两个态之间存在单光子和双光子过程两个激发路径，并且单光子过程和双光子过程可以共存。基于一种非微扰近似法结合拉普拉斯变换，本课题将研究Δ型三能级系统中由这两个激发路径的量子干涉导致的Fano类共振现象和相关动力学行为，探讨该Fano类共振出现的条件，研究其共振线型特征；考察系统参量，尤其是系统与控制场的总相位对该Fano类共振的影响。我们将进一步采用含时密耦法，在高激发态碱金属原子中进行相关数值模拟，并寻求对该Fano类共振的控制机理。项目预期将对Δ型三能级系统性质的研究起到积极的推动作用，并为以后的实验研究提供理论基础。

中文关键词： Δ-型三能级系统；对称性破缺；拉比振荡；反对称线型；Fano共振

英文摘要： Different from the three basic configurations classified as Λ,V and cascade three level system,the Δ-type three level configuration exist in the quantum system with broken symmetry such as chiral molecules and artificial atoms made of superconducting quantum circuits（SQC）. In 2012，the applicant found that Δ-type system can also be realized using Rydberg atom,to break its symmetry,an external static electric field was added. It was demonstrated theoretically and experimentally that there are two pathway: one-photon process and two-photon process between given intial and final states in the Δ-type system with broken symmetry, and one- and two-photon processes can coexist. Based on a nonperturbative theory and the approach of Laplace transform, the proposed research is to explore the properties of the Fano-like resonance induced by quantum interference of the two pathways in Δ-type three level system. We will discuss what is needed for the appearance of a Fano-like resonance and the interesting property of the Fano-like resonance in Δ-type system. The effect of the parameters, especially the effect of total phase on the Fano-like resonance will also be examined. Furthemore, we will investigated the expected Fano-like resonance in Rydberg alkali-metal atoms numerically by using time-dependent close-coupling method. Meanwhile the possible control mechanism will also be discussed. We hope that our investigation stimulates experiments and are of benefit to the study of Δ-type three level system.

英文关键词： Δ-type three level system;broken symmetry;Rabi oscillation;asymmetry profile;Fano resonance