arXiv:1912.05130 · Physical review. B./Physical review. B

Discrete time crystal in the gradient-field Heisenberg model

Bikun Li, John S. Van Dyke, Ada Warren, Sophia E. Economou, Edwin Barnes

Published Mar 6, 2020• 14 citations

Abstract

We show that time crystal phases, which are known to exist for disorder-based many-body localized systems, also appear in systems where localization is due to strong magnetic field gradients. Specifically, we study a finite Heisenberg spin chain in the presence of a gradient field, which can be realized experimentally in quantum dot systems using micromagnets or nuclear spin polarization. Our numerical simulations reveal time crystalline order over a broad range of realistic quantum dot parameters, as evidenced by the long-time preservation of spin expectation values and the asymptotic form of the mutual information. We also consider the undriven system and present several diagnostics for many-body localization that are complementary to those recently studied. Our results show that these nonergodic phases should be realizable in modest-sized quantum dot spin arrays using only demonstrated experimental capabilities.

DOI: 10.1103/physrevb.101.115303

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