摘要
本文研究量子输运中马约拉纳费米子与杂质自旋的相互作用,发现系统能够产生温差驱动的自旋相关电流,得到了马约拉纳费米子导致的热自旋流.在大温差下,马约拉纳费米子与量子点强耦合时,电流与门电压趋于线性关系,体现了马约拉纳费米子的鲁棒性,且马约拉纳费米子导致的自旋流具有振荡特性,其零点个数与杂质自旋角量子数相关.
In quantum transport,especially in spintronics,its central theme is to manipulate spin degrees of freedom in solid-state systems,to understand the interaction between the particle spin and its solid-state environments and to make useful devices.Recently,Majorana fermion has been introduced into quantum transport and received much attention.In this paper,we study a thermal-driven transport model which consists of a quantum dot coupled with two normal metal leads,a impurity spin(whose angular quantum number is more than or equal to one-half)and a Majorana fermion.We focus on the interplay between Majorana fermion and the impurity in this exactly solvable model.It is found that the system can generate thermal-induced spin current,and the currents are affected by Majorana fermion and impurity.With large temperature difference,the currents are sensitive to gate voltage,and the quantitative relation between spin-up current and gate voltage tends to be linear when the coupling between Majorana and quantum dot is strong,showing Majorana fermion’s robustness.In addition,the spin current induced by Majorana fermion exhibits an oscillating antisymmetric structure around zero-bias point.This spin current’s zero point is related to the angular quantum number of impurity spin.These results are expected to be useful in thermal-electric conversion devices,and may be observed in future experiments.
作者
牛鹏斌
罗洪刚
Niu Peng-Bin;Luo Hong-Gang(Department of Physics,Shanxi Datong University,Datong 037009,China;School of Physical Science and Technology,Lanzhou University,Lanzhou 730000,China)
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2021年第11期282-288,共7页
Acta Physica Sinica
基金
国家自然科学基金(批准号:11834005,11674139)资助的课题。
