量子点中电子自旋量子比特的声子效应研究

项目名称： 量子点中电子自旋量子比特的声子效应研究

项目编号： No.11264001

项目类型： 地区科学基金项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 尹辑文

作者单位： 赤峰学院

项目金额： 48万元

中文摘要： 当前低维系统如量子点、量子线、石墨烯等中电子自旋态的研究在未来新一代的量子器件中有着广泛的应用前景而成为当前物理学各个分支研究的热门。而基于量子点中电子自旋态方案实现量子计算机基本运算和信息存储单元的量子比特被认为是最具前景的方案之一，因此这一方面迅速成为凝聚态物理、固态量子信息与量子计算的研究热点。 本项目拟用线性组合算符方法、Pekar变分方法和晶格驰豫的多声子跃迁方法研究量子点中基于电子自旋的量子比特的声子效应。主要研究声子对电子自旋态的翻转弛豫，相干和消相干过程的影响，重点考虑在电子自旋与声子直接耦合机制下自旋翻转驰豫的双声子过程。同时进一步研究在Rashba和Dresselhaus效应影响下电子自旋的单声子和双声子自旋弛豫和消相干过程并对这两种效应的贡献进行区分。同时也对电子与多声子模式相互作用共同对自旋弛豫的影响及石墨烯量子点中狄拉克电子自旋弛豫进行探讨研究。

中文关键词： 量子点；石墨烯；自旋弛豫；自旋轨道耦合；量子比特

英文摘要： Low-dimensional systems such as quantum dots, quantum wires and graphene electron spin state has a broad application prospects in the next generation of quantum devices become popular of the various branches of the current physics research. Qubit quantum computer computing and information storage unit based on the state program of the electron spin in quantum dots to achieve is considered to be one of the most promising programs, so this quickly became the condensed matter physics, solid-state quantum information and quantum computation research focus. The project is intended to use the linear combination operator method, Pekar variational methods and lattice relaxation of the multi-phonon transition method of quantum dots based on electron spin qubits phonon effect. Flip relaxation of electron spin states, the main phonon coherent and decoherence in the process, the key consideration in the direct coupling mechanism of electron spin-phonon spin-flip relaxation of two-phonon processes. Further study the contribution of these two effects, and the Rashba and Dresselhaus effect of a single phonon of the electron spin and the spin relaxation and decoherence of two-phonon process to distinguish. But also the interaction of electronic and multi-phonon mode common to discuss the spin relaxation in graphene quantum dots

英文关键词： quantum dot；graphene；spin relaxation；spin orbital coupling；quantum bit