Topological nonlinear anomalous Nernst effect in strained transition metal dichalcogenides
Xiao-Qin Yu,^1,* Zhen-Gang Zhu,^2,3,4,† Jhih-Shih You,^5,‡ Tony Low,^6,§ and Gang Su ^3,7,4,
1School of Physics and Electronics, Hunan University, Changsha 410082, China
²School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
³Theoretical Condensed Matter Physics and Computational Materials Physics Laboratory, College of Physical Sciences,
University of Chinese Academy of Sciences, Beijing 100049, China
⁴CAS Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing 100190, China
⁵Institute for Theoretical Solid State Physics, IFW Dresden, Helmholtzstraße 20, 01069 Dresden, Germany
⁶Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA
⁷Kavli Institute of Theoretical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
(Received 2 March 2019; revised manuscript received 7 May 2019; published 20 May 2019)

We theoretically analyze the nonlinear anomalous Nernst effect as the second-order response of temperature gradient by using the semiclassical framework of electron dynamics. We find that a nonlinear current can be generated transverse to the applied temperature gradient in time-reversal-symmetry materials with broken inversion symmetry. This effect has a quantum origin arising from the Berry curvature of states near the Fermi surface. We discuss the nonlinear Nernst effect in transition metal dichalcogenides (TMDCs) under the application of uniaxial strain. In particular, we predict that under fixed chemical potential in TMDCs, the nonlinear Nernst current exhibits a transition from T −2 temperature dependence in low temperature regime to a linear T dependence in high temperature.