Work

Observation of continuous time crystals and quasi-crystals in spin gases

Year: 2025
Type: article
Abstract: Continuous time crystals (CTCs) are a phase of matter characterized by spontaneous breaking of continuous time-translation symmetry. Recently, CTCs have garnered interest due to breakthroughs in experimental implementation. Here we report the experimental observation of CTCs in noble-gas nuclear spins and uncover previously unexplored dynamical phenomena. We observe that the CTCs manifest as persistent limit cycle oscillations of nuclear spins, with coherence times exceeding hours. Notably, these oscillations are robust against noise perturbations and exhibit random time phases upon repetitive realization, epitomizing continuous time-translation symmetry-breaking intrinsic to CTCs. Additionally, we observe a dynamical phase featuring quasi-periodic oscillations and random time phases, indicating the emergence of the continuous time quasi-crystals proposed by recent theories. By varying the feedback strength and magnetic gradient, we observe complex dynamical phase transitions between time crystal phases and chaotic regimes. This work broadens the catalog of phases of spin gases and unlocks opportunities in precision measurements. The authors report on the observation of continuous time crystals of nuclear spins of 129Xe atoms within a Rb-Xe gaseous mixture in a magnetic feedback scheme. This unveils nontrivial role of magnetic fields and a new continuous time quasi-crystal phase.
Language: English
Open Access status: gold
Estimated APC paid: $6,990
OpenAlex ID: W4415464385
FWCI: 2.963
Cites: 50
Cited by: 8
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