From Dynamical Localization to Bunching in interacting Floquet Systems

TL;DR

This paper demonstrates how periodic Floquet driving can control the mobility and diffusion of excitations in many-body quantum systems, exemplified by the Fermi-Hubbard model, enabling manipulation of doublon dynamics and fermion pairing.

Contribution

It introduces a specific Floquet driving scheme to control excitations and diffusion in many-body systems, generalizing the approach beyond the Fermi-Hubbard model.

Findings

Diffusion can be completely suppressed under certain driving conditions.

Doublon dynamics determine fermion pairing and transport properties.

The control scheme is applicable to generic many-body systems.

Abstract

We show that a quantum many-body system may be controlled by means of Floquet engineering, i.e., their properties may be controlled and manipulated by employing periodic driving. We present a concrete driving scheme that allows control over the nature of mobile units and the amount of diffusion in generic many-body systems. We demonstrate these ideas for the Fermi-Hubbard model, where the drive renders doubly occupied sites (doublons) the mobile excitations in the system. In particular, we show that the amount of diffusion in the system and the level of fermion-pairing may be controlled and understood solely in terms of the doublon dynamics. We find that under certain circumstances the diffusion in the system may be eliminated completely. We conclude our work by generalizing these ideas to generic many-body systems.