Nonlocal thermoelectricity in a topological Andreev interferometer

Abstract

We discuss the phase-dependent nonlocal thermoelectric effect in a topological Josephson junction in contact with a normal-metal probe. We show that, due to the helical nature of topological edge states, nonlocal thermoelectricity is generated by a purely Andreev interferometric mechanism. This response can be tuned by imposing a Josephson phase difference, through the application of a dissipationless current between the two superconductors, even without the need of applying an external magnetic field. We discuss in detail the origin of this effect and we also provide a realistic estimation of the nonlocal Seebeck coefficient which turns out to be of the order of a few μV/K at temperatures of a few kelvin.