Stark time crystals: Symmetry breaking in space and time

TL;DR

This paper introduces Stark time crystals, a new phase of matter exhibiting symmetry breaking in space and time without requiring spatial disorder, advancing the understanding of time crystals and their potential applications.

Contribution

The work presents Stark time crystals based on localization without disorder, closely aligning with the original time crystal concept and expanding the theoretical framework.

Findings

Stark time crystals demonstrate symmetry breaking in space and time.

They can exist without spatial disorder, unlike traditional many-body localized systems.

Potential for practical applications with less stringent localization requirements.

Abstract

The compelling original idea of a time crystal has referred to a structure that repeats in time as well as in space, an idea that has attracted significant interest recently. While obstructions to realize such structures became apparent early on, focus has shifted to seeing a symmetry breaking in time in periodically driven systems, a property of systems referred to as discrete time crystals. In this work, we introduce Stark time crystals based on a type of localization that is created in the absence of any spatial disorder. We argue that Stark time crystals constitute a phase of matter coming very close to the original idea and exhibit a symmetry breaking in space and time. Complementing a comprehensive discussion of the physics of the problem, we move on to elaborating on possible practical applications and argue that the physical demands of witnessing genuine signatures of many-body localization in large systems may be lessened in such physical systems.