低维耦合量子体系中混合空穴基态及自旋调控研究

项目名称： 低维耦合量子体系中混合空穴基态及自旋调控研究

项目编号： No.61204105

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 信息四处

项目作者： 汤乃云

作者单位： 上海电力学院

项目金额： 24万元

中文摘要： 在量子计算、量子信息和光电子技术等方面的潜在应用，低维半导体量子结构的耦合调控逐渐受到广泛关注。本项目拟开展低维耦合量子体系中混合空穴基态的物理特性及电磁场下空穴自旋-轨道相互作用机理的研究，通过建立外电磁场下体系的轻重空穴耦合、自旋轨道作用、应变场和交换关联等模型，探讨不同空穴电荷分布对系统基态成键和反键特征的影响，揭示耦合空穴态的轨道特征和反交叉行为；基于波函数的分布，弄清轨道-自旋相互作用与耦合体系的对称性及距离的关系，实现磁场对空穴基态自旋分布的控制；进一步针对零维/一维耦合量子结构，通过调节量子结构间的量子隧穿和空穴态的关联，弄清限域体系自旋-轨道相互作用的空穴g因子与外场的关系，获得共振耦合条件下半导体耦合量子结构的空穴基态性质的演变及自旋分布。研究结果有助于深层次理解和认识低维耦合体系中空穴轨道和自旋分布的反常特征，为未来基于耦合体系的自旋量子调控应用提供相应的理论基础。

中文关键词： 耦合量子体系；空穴态；反键态；自旋；

英文摘要： Because of potential applications in novel optoelectronic devices or quantum information processing, the low dimensional coupled quantum systems have been the focus of much research.In this project, we aim at studying physical properties of the hole ground state and manipulation of hole spin under electric and magnetic fields in low dimensional coupled quantum systems. The main work include the following four points: (1)In coupled system, the electronic states, being bounding-like ground states, is mostly based on single-band effective-mass approximations, but the valence hole shows more complex feature. Since the two uppermost P-like valence band is subject to a strong spin-orbit (SO) interaction, which leads to a sizeable coupling of heavy-hole (HH) and light-hole (LH) subbands. Our studies showed that the ground states of a valence hole in coupled quantum dots show an anti-bounding-like character. By means of multi-band KoP approximation, We will investigate the properties of hole orbital taking into account the effects of LH-HH mixture, spin-orbit interaction, strain and exchange correlation. By revealing the coupling hole state orbit and anti-cross characteristics, The results can access to the key physical parameters of coupled quantum hole ground state in low-dimensional system . (2)We will study correla

英文关键词： coupled quantum systems；hole ground；anti-bounding-like character；spin；