Light-induced switching between singlet and triplet superconducting states

TL;DR

This paper proposes a theory where tailored light pulses can switch a superconductor between singlet and triplet states, offering a new non-equilibrium method to realize topological superconductivity.

Contribution

It introduces a model showing how optical pulses can induce parity-changing superconducting state transitions in materials with strong spin-orbit coupling.

Findings

Light pulses can induce odd-parity triplet order oscillations.

Dynamical inversion symmetry breaking enables switching between superconducting states.

The approach suggests a non-equilibrium pathway to topological superconductivity.

Abstract

While the search for topological triplet-pairing superconductivity has remained a challenge, recent developments in optically stabilizing metastable superconducting states suggest a new route to realizing this elusive phase. Here, we devise a testable theory of competing superconducting orders that permits ultrafast switching to an opposite-parity superconducting phase in centrosymmetric crystals with strong spin-orbit coupling. Using both microscopic and phenomenological models, we show that dynamical inversion symmetry breaking with a tailored light pulse can induce odd-parity (spin triplet) order parameter oscillations in a conventional even-parity (spin singlet) superconductor, which when driven strongly can send the system to a competing minimum in its free energy landscape. Our results provide new guiding principles for engineering unconventional electronic phases using light, suggesting a fundamentally non-equilibrium route toward realizing topological superconductivity.