- Letter
Dissipation-enhanced nonreciprocal superconductivity: Application to multivalley superconductors
Phys. Rev. Applied 24, L031004 – Published 15 September, 2025
DOI: https://doi.org/10.1103/n681-k9dl
Abstract
Herein, we propose and theoretically study a nonequilibrium mechanism for the superconducting diode effect, which applies specifically to the case where time-reversal symmetry—a prerequisite for the diode effect—is spontaneously broken by the superconducting electrons themselves. We employ a generalized time-dependent Ginzburg-Landau formalism to capture dissipation effects in the nonequilibrium current-carrying state via phase slips and show that the coupling of the resistive current to the symmetry-breaking order is enough to induce a diode effect. Depending on parameters, the critical-current asymmetry can be sizeable, asymptotically reaching a perfect diode efficiency; the competition between symmetry-breaking order, superconducting currents, and resistive currents gives rise to rich physics, such as current-stabilized, nonequilibrium superconducting correlations. Although our mechanism is more general, the findings are particularly relevant to twisted trilayer and rhombohedral tetralayer graphene, where the symmetry-breaking order parameter refers to the imbalance of the two valleys of the systems.