Negative tunnel magnetoresistance in a quantum dot induced by interplay of a Majorana fermion and thermal-driven ferromagnetic leads  

作　　者：Peng-Bin Niu Bo-Xiang Cui Hong-Gang Luo 牛鹏斌;崔博翔;罗洪刚(Department of Physics,Shanxi Datong University,Datong 037009,China;School of Physical Science and Technology,Lanzhou University,Lanzhou 730000,China;Beijing Computational Science Research Center,Beijing 100084,China)

机构地区：[1]Department of Physics,Shanxi Datong University,Datong 037009,China [2]School of Physical Science and Technology,Lanzhou University,Lanzhou 730000,China [3]Beijing Computational Science Research Center,Beijing 100084,China

出　　处：《Chinese Physics B》2021年第9期495-498,共4页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.11834005 and 11674139).

摘　　要：We investigate the spin-related currents and tunnel magnetoresistance through a quantum dot,which is side-coupled with a Majorana fermion zero mode and two thermal-driven ferromagnetic electrodes.It is found that the interplay of Majorana fermion and electrodes'spin polarization can induce a nonlinear thermal-bias spin current.This interplay also decreases the total magnitude of spin or charge current,in either parallel or antiparallel configuration.In addition,a thermal-driven negative tunnel magnetoresistance is found,which is an unique feature to characterize Majorana fermion.With large temperature difference,a step phenomenon is observed in gate tuned spin-up current.When the coupling between quantum dot and topological superconductor is strong enough,this step will evolve into a linear relation,revealing Majorana fermion's robustness.

关 键 词：Majorana fermion spin current tunnel magnetoresistance thermal-bias 

分 类 号：O469[理学—凝聚态物理]