Suppression of heating in quantum spin clusters under periodic driving as a dynamic localization effect

TL;DR

This paper studies how periodic magnetic pulses can suppress heating in quantum spin clusters through a dynamic localization effect, with a threshold that diminishes as cluster size grows, approaching zero in large systems.

Contribution

It introduces a quantitative threshold condition for heating suppression in interacting spin clusters, linking dynamic localization to the breakdown of the golden rule.

Findings

Heating is suppressed below a certain pulse strength threshold.

The threshold decreases with increasing cluster size, tending to zero in the thermodynamic limit.

Dynamic localization causes the suppression of heating in quantum spin systems.

Abstract

We investigate numerically and analytically the heating process in ergodic clusters of interacting spins 1/2 subjected to periodic pulses of external magnetic field. Our findings indicate that there is a threshold for the pulse strength below which the heating is suppressed. This threshold decreases with the increase of the cluster size, approaching zero in the thermodynamic limit; yet it should be observable in clusters with fairly large Hilbert spaces. We obtain the above threshold quantitatively as a condition for the breakdown of the golden rule in the second-order perturbation theory. It is caused by the phenomenon of dynamic localization.