Higher-harmonic generation in the driven Mott-Hubbard model

TL;DR

This paper investigates the non-equilibrium behavior of a Mott insulator under periodic driving, revealing optimal conditions for higher-harmonic generation when the driving frequency is one-third of the Mott gap.

Contribution

It introduces a Floquet-based approach combined with hierarchy of correlations to analyze higher-harmonic generation in the driven Fermi-Hubbard model.

Findings

Maximum harmonic signal occurs at one-third of the Mott gap frequency.

Derived Floquet exponents characterize the non-equilibrium dynamics.

Provides insights into controlling high-harmonic generation in correlated materials.

Abstract

Using Floquet theory and the hierarchy of correlations, we study the non-equilibrium dynamics of the Mott insulator state in the Fermi-Hubbard model under the influence of a harmonically oscillating electric field representing the pump laser. After deriving the associated Floquet exponents, we consider higher-harmonic generation where the strongest signal is obtained if the driving frequency equals one third of the Mott gap.