Emergence of nonequilibrium Lieb excitations in periodically driven strongly interacting bosons

TL;DR

This paper investigates how strong periodic driving induces nonequilibrium Lieb excitations in strongly interacting bosons, revealing linear Lieb modes and Floquet-Fermi sea formation through exact spectral analysis.

Contribution

It introduces a novel exact analysis of nonequilibrium spectral functions showing emergent Lieb excitations in driven bosonic systems using Floquet theory and Bose-Fermi mapping.

Findings

Emergence of nonequilibrium Lieb modes in driven bosons

Linear Lieb excitations observed at low frequencies

Mapped fermions exhibit Dirac-like linear dispersion

Abstract

We study the exact nonequilibrium spectral function of a gas of strongly correlated Tonks-Girardeau bosons subjected to a strong periodic drive. Utilizing the theory of Floquet spectral function in conjunction with the Bose-Fermi mapping theorem, we show that nonequilibrium Lieb modes emerge if the underlying mapped fermions form a Floquet-Fermi sea. In the low-frequency regime, the exact analysis reveals the emergence of characteristic linear Lieb excitations for the bosonic system, while the underlying mapped fermions displays the wide Dirac-like linear dispersion.