The isolated Heisenberg magnet as a quantum time crystal
Abstract
We demonstrate analytically and numerically that the paradigmatic model of quantum magnetism, the Heisenberg XXZ spin chain, does not relax to stationarity and hence constitutes a genuine time crystal that does not rely on external driving or coupling to an environment. We trace this phenomenon to the existence of extensive dynamical symmetries and find their frequency to be a no-where continuous (fractal) function of the anisotropy parameter of the chain. We discuss how the ensuing persistent oscillations that violate one of the most fundamental laws of physics could be observed experimentally and identify potential metrological applications.
Keywords
Cite
@article{arxiv.1905.08266,
title = {The isolated Heisenberg magnet as a quantum time crystal},
author = {Marko Medenjak and Berislav Buca and Dieter Jaksch},
journal= {arXiv preprint arXiv:1905.08266},
year = {2020}
}
Comments
Main text: 5 pages, 2 figures; Supplementary: 4 pages, 1 figure. New version contains study of stability to integrability breaking