HgTe拓扑量子点少电子系统电子结构性质理论研究

项目名称： HgTe拓扑量子点少电子系统电子结构性质理论研究

项目编号： No.11304306

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 娄文凯

作者单位： 中国科学院半导体研究所

项目金额： 25万元

中文摘要： 拓扑绝缘体因其具有无耗散金属边缘态或表面态，在新一代的量子计算和自旋电子学器件方面有潜在应用前景，而成为凝聚态物理领域近期研究热点。窄禁带半导体HgTe材料是反转带隙，具有很强自旋轨道耦合效应，是实现拓扑绝缘体相的理想材料。拓扑量子点与块材料相比具有更大表面积体积比，对研究拓扑绝缘体表面态有更明显优势。对拓扑量子点少电子系统量子态准确描述，将为开发拓扑绝缘体在未来量子计算和量子信息处理中的器件应用铺平道路。因此发展拓扑量子点少电子系统理论很有必要，但是相关报道却很少。本项目拟从八带k.p模型出发，约化出包括电子态和重、轻空穴态的六带有效哈密顿量，并将此六带有效哈密顿量模型和构型方法结合，发展拓扑绝缘体量子点少电子系统理论。我们将细致研究外场对HgTe拓扑量子点少电子系统电子结构影响。本项目对于深化对HgTe拓扑量子点少电子系统物理性质的理解和实现拓扑绝缘体量子点的器件应用具有重要指导意义。

中文关键词： 拓扑绝缘体；量子点；少电子；构型方法；库伦相互作用

英文摘要： Topological insulator, owing to its nondissipative metallic edge states (or surface states) and potential applications in a new generation of quantum computing and spintronics devices, has become a recent hotspot in condensed matter physics. Since narrow gap semiconductor HgTe has an inverted band structure and strong spin-orbit interaction, it is an idea material to realize topological insulator phase. Compared to the bulk material, topological insulator quantum dot has larger surface-to-volume ratios, therefore it has obvious advantages on the study of topological insulator surface states. Accurate description of quantum states in topological quantum dot few electrons system will pave the way for the development of topological insulator devices application in future quantum computing and quantum information processing. The development of a theory of the topological quantum dot few electrons systems is necessary, but rarely reports. In this project, we will start from the eight band k.p model and reduce a six band effective Hamiltonian, which contains electron states, heavy hole and light hole states. Combing with configuration interaction method and this six band effective model, we will try to develop a theory of topological insulator quantum dot few electrons system. We will be careful to study the impact of

英文关键词： Topological Insulator；quantum dot；few electrons；Configuration Interaction method；Coulomb interaction