Engineering micromotion in Floquet prethermalization via space-time symmetries

TL;DR

This paper develops a systematic framework for Floquet prethermalization that highlights the importance of dynamical space-time symmetries, enabling better understanding and control of micromotion in driven quantum systems.

Contribution

It introduces a novel approach linking dynamical space-time symmetries to static symmetry groups and provides techniques for detecting these symmetries through local observable dynamics.

Findings

Demonstrates how space-time symmetries influence micromotion in Floquet systems

Provides a protocol to preserve specific dynamical symmetries in a spin-ladder model

Confirms relationships between local observable expectations at different Floquet cycle points

Abstract

We present a systematic framework for Floquet prethermalization under strong resonant driving, emphasizing the pivotal role of dynamical space-time symmetries. Our approach demonstrates how dynamical space-time symmetries map onto the projective static symmetry group of the prethermal Hamiltonian governing the prethermal regime. We introduce techniques for detecting dynamical symmetries through the time evolution of local observables, facilitating a detailed analysis of micromotion within each period and surpassing the limitations of conventional stroboscopic Floquet prethermal dynamics. To implement this framework, we present a prethermal protocol that preserves order-two dynamical symmetry in a spin-ladder model, confirming the predicted relationships between the expectation values of local observables at distinct temporal points in the Floquet cycle, linked by this symmetry.