Superconducting Berry Curvature Dipole

Abstract

Superconductivity and Bloch band Berry curvature responses represent two distinct paradigms of quantum coherent phenomena. The former relies on the collective motion of Cooper pairs while the latter proceeds from the momentum-space winding of Bloch wave functions. Here we reveal a superconducting Berry curvature dipole (BCD) that arises as a collective phenomenon in noncentrosymmetric superconductors. Strikingly, we find the superconducting BCD is sensitive to the phase of the order parameter and depends on the noncentrosymmetric structure of its pairing. This unusual property enables a BCD proximity effect in hybrid quantum materials that induces nonreciprocity even in a target centrosymmetric metal. We find a superconducting BCD naturally produces nonreciprocal electromagnetic responses that include dissipationless supercurrent-induced dynamical Hall conductivity as well as a giant second-order nonlinearity. This renders noncentrosymmetric superconductors an exciting platform for realizing unconventional dissipationless responses and their BCD responses a novel diagnostic of the structure of the superconducting gap.