We demonstrate that the supercurrent can be strongly enhanced in cross-like superconducting hybrid nanostructures (X-junctions) exposed to a temperature gradient. At temperatures T exceeding the Thouless energy of our X-junction the Josephson current decays algebraically with increasing T and can be further enhanced by a proper choice of the circuit topology. At large values of the temperature gradient the non-equilibrium contribution to the supercurrent may become as large as the equilibrium one at low T. We also predict a variety of transitions between 0- and π-junction states controlled by the temperature gradient as well as by the system geometry. Our predictions can be directly verified in modern experiments.
@article{arxiv.2012.07366,
title = {Long-range Josephson effect controlled by temperature gradient and circuit topology},
author = {Mikhail S. Kalenkov and Andrei D. Zaikin},
journal= {arXiv preprint arXiv:2012.07366},
year = {2021}
}