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arXiv · 1611.09724

Thermoelectric transport in junctions of Majorana and Dirac channels

Dmitriy S. Shapiro·D. E. Feldman·Alexander D. Mirlin·Alexander Shnirman
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Abstract

We investigate the thermoelectric current and heat conductance in a chiral Josephson contact on a surface of a 3D topological insulator, covered with superconducting and magnetic insulator films. The contact consists of two junctions of Majorana and Dirac channels next to two superconductors. Geometric asymmetry results in a supercurrent without a phase bias. The interference of Dirac fermions causes oscillations of the electric and heat currents with an unconventional period $2\Phi_0=h/e$ as functions of the Aharonov-Bohm flux. Due to the gapless character of Majorana modes, there is no threshold for the thermoelectric effect and the current-flux relationship is non-sinusoidal. Depending on the magnetic flux, the direction of the electric current can be both from the hot to cold lead and vice versa.

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Dmitriy S. Shapiro, D. E. Feldman, Alexander D. Mirlin, Alexander Shnirman. 2016-11-29. Thermoelectric transport in junctions of Majorana and Dirac channels. https://doi.org/10.1103/physrevb.95.195425

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