Twisted chiral superconductivity in photodoped frustrated Mott insulators

TL;DR

This paper predicts a new chiral superconducting phase in photodoped frustrated Mott insulators, characterized by a spatially varying order parameter with broken symmetries, tunable via external fields and periodic driving.

Contribution

It introduces a novel metastable chiral superconducting phase with a 120° phase twist, stabilized by photodoping and external fields in frustrated Mott insulators.

Findings

The phase exhibits a second-order supercurrent perpendicular to an electric pulse.

The chiral state breaks time-reversal and inversion symmetry.

It can be realized in cold-atom simulators and correlated materials.

Abstract

Recent advances in ultrafast pump-probe spectroscopy provide access to hidden phases of correlated matter, including light-induced superconducting states, but the theoretical understanding of these nonequilibrium phases remains limited. Here we report how a new type of chiral superconducting phase can be stabilized in photodoped frustrated Mott insulators. The metastable phase features a spatially varying order parameter with a $120^\circ$ phase twist which breaks both time-reversal and inversion symmetry. Under an external electric pulse, the $120^\circ$ chiral superconducting state can exhibit a second-order supercurrent perpendicular to the field in addition to a first-order parallel response, similar to a nonlinear anomalous Hall effect. This phase can be tuned by artificial gauge fields when the system is dressed by high-frequency periodic driving. The mechanism revealed in this study applies to Mott insulators on various frustrated lattices and the hidden superconducting phase can be realized in both cold-atom quantum simulators and correlated solids.