Tuning between continuous time crystals and many-body scars in long-range XYZ spin chains

• URL: http://arxiv.org/abs/2205.02246v1
• Date: Wed, 4 May 2022 18:00:03 GMT
• Title: Tuning between continuous time crystals and many-body scars in long-range XYZ spin chains
• Authors: Kieran Bull, Andrew Hallam, Zlatko Papi\'c, Ivar Martin
• Abstract summary: We investigate the possibility of a emphcontinuous time crystal (CTC) in undriven, energy-conserving systems exhibiting prethermalization. We map out the dynamical phase diagram using numerical simulations based on exact diagonalization and time-dependent variational principle in the thermodynamic limit. We identify a regime where QMBS and CTC order co-exist, and we discuss experimental protocols that reveal their similarities as well as key differences.
• Score: 0.13764085113103217
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Persistent oscillatory dynamics in non-equilibrium many-body systems is a tantalizing manifestation of ergodicity breakdown that continues to attract much attention. Recent works have focused on two classes of such systems: discrete time crystals and quantum many-body scars (QMBS). While both systems host oscillatory dynamics, its origin is expected to be fundamentally different: discrete time crystal is a phase of matter which spontaneously breaks the $\mathbb{Z}_2$ symmetry of the external periodic drive, while QMBS span a subspace of non-thermalizing eigenstates forming an su(2) algebra representation. Here we ask a basic question: is there a physical system that allows to tune between these two dynamical phenomena? In contrast to much previous work, we investigate the possibility of a \emph{continuous} time crystal (CTC) in undriven, energy-conserving systems exhibiting prethermalization. We introduce a long-range XYZ spin model and show that it encompasses both a CTC phase as well as QMBS. We map out the dynamical phase diagram using numerical simulations based on exact diagonalization and time-dependent variational principle in the thermodynamic limit. We identify a regime where QMBS and CTC order co-exist, and we discuss experimental protocols that reveal their similarities as well as key differences.

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