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arXiv · 2105.01527

Spontaneous symmetry breaking-induced thermospin effect in superconducting tunnel junctions

Gaia Germanese·Federico Paolucci·Giampiero Marchegiani·Alessandro Braggio·Francesco Giazotto
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Abstract

We discuss the charge and the spin tunneling currents between two Bardeen-Cooper-Schrieffer (BCS) superconductors, where one density of states is spin-split. In the presence of a large temperature bias across the junction, we predict the generation of a spin-polarized thermoelectric current. This thermo-spin effect is the result of a spontaneous particle-hole symmetry breaking in the absence of a polarizing tunnel barrier. The two spin components, which move in opposite directions, generate a spin current larger than the purely polarized case when the thermo-active component dominates over the dissipative one.

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Gaia Germanese, Federico Paolucci, Giampiero Marchegiani, Alessandro Braggio, Francesco Giazotto. 2021-10-27. Spontaneous symmetry breaking-induced thermospin effect in superconducting tunnel junctions. https://doi.org/10.1103/physrevb.104.184502

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