自旋轨道耦合串联双量子点系统的电流有限频率噪声谱  

Finite-frequency Shot Noise of Electron Transport in a Serially Coupled Double Quantum Dot System with Spin-orbit Coupling

作　　者：马骁燕 段志磊 薛海斌 MA Xiaoyan;DUAN Zhilei;XUE Haibin(Key Laboratory of Interface Science and Engineering in Advanced Materials of the Ministry of Education,Taiyuan University of Technology,Taiyuan 030024,China;College of Physics and Optoelectronics,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学新材料界面科学与工程教育部重点实验室,山西太原030024 [2]太原理工大学物理与光电工程学院,山西太原030024

出　　处：《山西大学学报（自然科学版）》2021年第6期1114-1122,共9页Journal of Shanxi University(Natural Science Edition)

基　　金：山西省应用基础研究计划项目(201601D011015);山西省高等学校优秀青年学术带头人支持计划(163220120-S)。

摘　　要：文章基于粒子数分辨的量子主方程,研究了串联耦合双量子点中,自旋轨道耦合依赖的电流有限频率噪声谱。研究发现,在电流有限频率噪声谱上,其峰、谷的存在起源于串联耦合双量子点的量子相干性,而峰、谷的位置取决于其约化密度矩阵非对角元相应的能量本征值之差。其中,谷对应于非对角元相应的能量本征值之差简并度为2的情形,而峰则对应于简并度为1的情形。因此,可以通过电流有限频率噪声谱在不同外加磁场情形下的峰和谷位置,来确定自旋轨道耦合场参数的大小和量子点之间自旋守恒的电子跳跃隧穿强度。We study the finite-frequency shot noise of electron transport through a serially coupled double quantum dot(QD) system with spin-orbit coupling based on an effective particle number resolved quantum master equation. It is demonstrated that the existence of peaks and dips of the finite-frequency shot noise results from the quantum coherence of the serially coupled double QD system, whereas the positions of peaks and dips are determined by the eigenenergy differences of the coherent singly-occupied eigenstates that forming the off-diagonal elements of the reduced density matrix. Moreover, the peaks and dips correspond to the degeneracy of the corresponding energy difference, which are one and two, respectively. Therefore, we can quantitatively determine the magnitude of the SOC and the electron hopping strength of spin conservation between the two QDs based on the positions of peaks and dips of the finite-frequency shot noise for different values of the external magnetic field.

关 键 词：串联耦合双量子点 自旋轨道耦合 有限频率噪声谱 

分 类 号：O413[理学—理论物理]