Exotic Freezing of Response in Quantum Many-Body System

TL;DR

This paper reveals a novel non-monotonic freezing behavior in quantum many-body systems under high-frequency periodic driving, driven by quantum coherence effects absent in classical systems.

Contribution

It introduces the concept of exotic, non-monotonic response freezing in quantum systems, supported by analytical and numerical analysis of integrable quantum spin models.

Findings

Freezing peaks occur at specific driving parameters due to quantum coherence.

The response exhibits a non-monotonic, peak-valley structure with frequency.

Quantum systems can nearly freeze dynamically at certain parameters, unlike classical systems.

Abstract

We show that when a quantum many-body system is subjected to coherent periodic driving, the response may exhibit exotic freezing behavior in high driving frequency ($\omega$) regime. In a periodically driven classical thermodynamic system, freezing at high $\omega$ occurs when $1/\omega$ is much smaller than the characteristic relaxation time of the system, and hence the freezing always increases there as $\omega$ is increased. Here, in the contrary, we see surprising non-monotonic freezing behavior of the response with $\omega$, showing curious peak-valley structure. Quite interestingly, the entire system tends to freeze almost absolutely (the freezing peaks) when driven with a certain combination of driving parameters values (amplitude and $\omega$) due to coherent suppression of dynamics of the quantum many-body modes, which has no classical analog. We demonstrate this new freezing phenomenon analytically (supported by large-scale numerics) for a general class of integrable quantum spin systems.