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arXiv · 1812.10923

Fractional Time Crystals

Pawel Matus·Krzysztof Sacha
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Abstract

Time crystals are quantum systems which are able to reveal condensed matter behavior in the time domain. It is known that crystalization in time can be observed in a periodically driven many-body system when interactions between particles force a system to evolve with a period which is an integer multiple of a driving period. This phenomenon is dubbed discrete time crystal formation. Here, we consider ultra-cold atoms bouncing on an oscillating atom mirror and show that the system can spontaneously form a discrete time crystal where the ratio of a period of its motion and a driving period is a rational number. This kind of discrete time crystals requires higher order resonant driving which is analyzed here with the help of an original approach.

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Pawel Matus, Krzysztof Sacha. 2018-12-28. Fractional Time Crystals. https://doi.org/10.1103/physreva.99.033626

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