耦合Majorana束缚态下铁磁-量子点-超导系统的自旋相关热电特性  

Spin-Dependent Thermoelectric Properties of Ferromagnetic-Quantum Dot-Superconducting Systems Coupled to Majorana Bound States

作　　者：温祥 王强[2] WEN Xiang;WANG Qiangh(College of Computer Science and Technology,Taiyuan Normal University,Jinzhong Shanxi 030619,China;Department of Physics,Taiyuan Normal University,Jinzhong Shanxi 030619,China)

机构地区：[1]太原师范学院计算机科学与技术学院,山西晋中030619 [2]太原师范学院物理系,山西晋中030619

出　　处：《太原师范学院学报(自然科学版)》2025年第1期61-71,共11页Journal of Taiyuan Normal University:Natural Science Edition

基　　金：山西省应用基础研究计划项目(201901D211425,202103021223319);山西省高等学校科技创新项目(2021L417)。

摘　　要：利用非平衡格林函数和运动方程方法,从理论上研究了侧耦合Majorana束缚态铁磁-量子点-超导体系的自旋相关热电特性.研究发现,量子点与Majorana束缚态的耦合强度会使系统的热电和热自旋转换效率发生同量级的增大或减小.热电和热自旋转换效率可以通过增大Majorana束缚态间的耦合能量与增加铁磁电极的自旋极化率来进一步提高.此外,通过Andreev反射电导峰的数量和位置以及自旋热电势的符号反转现象,所研究系统可以实现对Majorana束缚态及其与量子点间耦合状态的探测.By utilizing non-equilibrium Green's function and equation of motion method,theo-retically investigate the spin-dependent thermoelectric properties of a ferromagnetic-quantum dot-superconducting system coupled to the Majorana bound state.The study reveals that the coupling strength between the quantum dot and the Majorana bound states can cause the thermoelectric and thermal spin conversion efficiencies of the system to increase or decrease by the same order of magni-tude.These efficiencies can be further enhanced by increasing the coupling energy between the Majo-rana bound states and by raising the spin polarization of the ferromagnetic electrode.In addition,through the number and position of Andreev reflection conductance peaks,as well as the sign reversal phenomenon of the spin thermopower,,the system under investigation can be used to probe the Majo-rana bound states and their coupling states with the quantum dot.

关 键 词：量子点 超导结构 Majorana束缚态 热电和热自旋效应 

分 类 号：O469[理学—凝聚态物理]