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arXiv · 2404.05620

Experimental observation of a time rondeau crystal: Temporal Disorder in Spatiotemporal Order

Leo Joon Il Moon·Paul Manuel Schindler·Yizhe Sun·Emanuel Druga·Johannes Knolle·Roderich Moessner·Hongzheng Zhao·Marin Bukov·Ashok Ajoy
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Abstract

Our understanding of phases of matter relies on symmetry breaking, one example being water ice whose crystalline structure breaks the continuous translation symmetry of space. Recently, breaking of time translation symmetry was observed in systems not in thermal equilibrium. The associated notion of time crystallinity has led to a surge of interest, raising the question about the extent to which highly controllable quantum simulators can generate rich and tunable temporal orders, beyond the conventional classification of order in static systems. Here, we investigate different kinds of partial temporal orders, stabilized by non-periodic yet structured drives, which we call rondeau order. Using a $^{13}$C-nuclear-spin diamond quantum simulator, we report the first experimental observation of a -- tunable degree of -- short-time disorder in a system exhibiting long-time stroboscopic order. This is based on a novel spin control architecture that allows us to implement a family of drives ranging from structureless via structured random to quasiperiodic and periodic drives. Leveraging a high throughput read-out scheme, we continuously observe the spin polarization over 105 pulses to probe rondeau order, with controllable lifetimes exceeding 4 seconds. Using the freedom in the short-time temporal disorder of rondeau order, we show the capacity to encode information in the response of observables. Our work broadens the landscape of observed nonequilibrium temporal order, paving the way for new applications harnessing driven quantum matter.

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Leo Joon Il Moon, Paul Manuel Schindler, Yizhe Sun, Emanuel Druga, Johannes Knolle, Roderich Moessner, Hongzheng Zhao, Marin Bukov, Ashok Ajoy. 2024-04-08. Experimental observation of a time rondeau crystal: Temporal Disorder in Spatiotemporal Order. https://doi.org/10.1038/s41567-025-03028-y

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