Dynamical order and superconductivity in a frustrated many-body system

TL;DR

This study investigates how driving a frustrated triangular Hubbard model out of equilibrium influences its complex states, revealing a mechanism that induces long-range order and impacts photo-induced superconductivity.

Contribution

It uncovers a novel dynamical mechanism where driving suppresses particle-hole excitations, leading to uniform long-range order in a frustrated many-body system.

Findings

Driving suppresses particle-hole excitations unexpectedly.

Long-range order emerges due to dynamical constraints.

Implications for photo-induced superconductivity experiments.

Abstract

In triangular lattice structures, spatial anisotropy and frustration can lead to rich equilibrium phase diagrams with regions containing complex, highly entangled states of matter. In this work we study the driven two-rung triangular Hubbard model and evolve these states out of equilibrium, observing how the interplay between the driving and the initial state unexpectedly shuts down the particle-hole excitation pathway. This restriction, which symmetry arguments fail to predict, dictates the transient dynamics of the system, causing the available particle-hole degrees of freedom to manifest uniform long-range order. We discuss implications of our results for a recent experiment on photo-induced superconductivity in ${\rm \kappa - (BEDT-TTF)_{2}Cu[N(CN)_{2}]Br}$ molecules.