Large valley Nernst effect in twisted multilayer graphene systems  

作　　者：简冠林 朱振刚 苏刚 Guanlin Jian;Zhen-Gang Zhu;Gang Su(School of Physical Sciences,University of Chinese Academy of Sciences,Beijing 100049,China;School of Electronic,Electrical and Communication Engineering,University of Chinese Academy of Sciences,Beijing 100049,China;CAS Center for Excellence in Topological Quantum Computation,University of Chinese Academy of Sciences,Beijing 100190,China;Kavli Institute for Theoretical Sciences,University of Chinese Academy of Sciences,Beijing 100190,China)

机构地区：[1]School of Physical Sciences,University of Chinese Academy of Sciences,Beijing 100049,China [2]School of Electronic,Electrical and Communication Engineering,University of Chinese Academy of Sciences,Beijing 100049,China [3]CAS Center for Excellence in Topological Quantum Computation,University of Chinese Academy of Sciences,Beijing 100190,China [4]Kavli Institute for Theoretical Sciences,University of Chinese Academy of Sciences,Beijing 100190,China

出　　处：《Chinese Physics B》2023年第10期22-30,共9页中国物理B（英文版）

基　　金：Project supported in part by the National Key R&D Program of China(Grant No.2018YFA0305800);the National Natural Science Foundation of China(Grant Nos.11974348 and 11834014);supported by the Strategic Priority Research Program of Chinese Academy of Sciences(Grant Nos.XDB28000000 and XDB33000000);supported in part by the Training Program of Major Research plan of the National Natural Science Foundation of China(Grant No.92165105);CAS Project for Young Scientists in Basic Research(Grant No.YSBR-057)。

摘　　要：Valley Nernst effect is a newly proposed and experimentally confirmed effect,which could be used to design novel thermoelectric devices.We study the valley Nernst effect in(M+N)-layer twisted multilayer graphene systems by a simple low-energy effective model.It is found that the total valley Nernst coefficient(VNC)is three orders of magnitude larger than that in monolayer group-Ⅵdichalcogenides.The total VNC increases with the increase of layer numbers.It is shown that the total VNC exhibits a structure with three peaks as a function of the Fermi energy.We identify that the central peak is always negative stemming from the flat band.Two shoulder peaks are positively induced by the conduction and valence bands,respectively.These predicted features can be tested experimentally.The present work would shed more light on valley caloritronics.

关 键 词：valley Nernst effect twisted multilayer graphene 

分 类 号：O469[理学—凝聚态物理]