Nonequilibrium orders in parametrically driven field theories

TL;DR

This paper develops a field theoretical framework to describe nonequilibrium phases, such as time-crystalline states, induced by rapid parametric drives in O(N) models relevant to condensed matter systems.

Contribution

It introduces a novel theoretical approach to analyze nonequilibrium phases caused by parametric driving in condensed matter models, highlighting the emergence of time-crystalline order.

Findings

Parametric drives induce effective pump mechanisms via nonlinear scattering.

Rapid driving can lead to a nonequilibrium transition into a time-crystalline phase.

The framework applies to long-wavelength fluctuations in condensed matter systems.

Abstract

Driving quantum materials with coherent light has proven a powerful platform to realize a plethora of interesting phases and transitions, ranging from ferroelectricity to superconductivity and limit cycles in pumped magnonics. In this paper we develop the field theoretical framework to describe nonequilibrium phases that emerge in systems pumped by rapid parametric drives. We consider paradigmatic O(N) models that describe the long-wavelength fluctuations of ordering fields in many condensed matter set ups. We show that rapid parametric driving of these models can induce an effective pump mechanism in the long wavelength regime through nonlinear scattering. This induces a nonequilibrium transition into a time-crystalline phase.