Thermoelectric transport in the topological phase due to the coexistence of superconductivity and spin-density-wave

TL;DR

This paper investigates thermoelectric transport in a two-dimensional topological system with coexisting superconductivity and spin-density wave order, revealing topological phases and analyzing surface and bulk contributions to transport.

Contribution

It introduces a model of coexistence of unconventional superconductivity and SDW, showing the emergence of topological phases and analyzing their transport properties.

Findings

Topological phases arise in the coexistence of SC and SDW.

Surface/edge and bulk transport contributions are distinct and competitive.

Possibility of enhancing thermoelectric figure of merit in such systems.

Abstract

We study the thermoelectric transport in two dimensional topological system which has coexistence of superconductivity(SC) and spin-density wave(SDW). The SC is presumed to be of $d_{x^2-y^2}+(p_x + i p_y) $ type whereas the SDW order parameter is of $BCS$ symmetry. The Hamiltonian describing such a coexistence phase is shown to have topological phase in addition to the conventional one. The transport properties in such topological system have two distinct contributions: (i) the surface/edge and (ii) the bulk. The competition between the surface/edge versus the bulk transport is analyzed in different parameter regimes and the possibility of enhancing the figure of merit is discussed.