近日，北京大学赵宏政团队报道了实验观测到时间回旋晶体。这一研究成果发表在2025年10月14日出版的《自然—物理学》杂志上。

物质常规相可通过其破坏的对称性来表征，例如冰的晶体结构破坏了空间的连续平移对称性。近年来，非平衡系统中观测到时间平移对称性的破缺，由此产生了所谓的时间晶体。

课题组研究了一种由非周期性结构化驱动稳定的部分时间序，称之为回旋序。以金刚石中碳-13核自旋作为量子模拟器，研究组利用微波驱动场在呈现长时频闪有序的系统中创建可调谐的短时无序。自旋控制架构使其能够实现包括周期性、非周期性和结构化随机驱动在内的多种驱动场。

通过高通量读取方案持续观测自旋极化及其回旋序，可控寿命超过4秒。利用回旋序短时无序相关的自由度，研究组演示了在可观测量响应中编码信息的能力。这项工作拓展了已观测到的非平衡时间序图谱，并展望了驱动量子物质的潜在应用前景。

附：英文原文

Title: Experimental observation of a time rondeau crystal

Author: Moon, Leo Joon Il, Schindler, Paul M., Sun, Yizhe, Druga, Emanuel, Knolle, Johannes, Moessner, Roderich, Zhao, Hongzheng, Bukov, Marin, Ajoy, Ashok

Issue&Volume: 2025-10-14

Abstract: Conventional phases of matter can be characterized by the symmetries they break, one example being water ice whose crystalline structure breaks the continuous translation symmetry of space. Recently, breaking of time-translation symmetry was observed in non-equilibrium systems, producing so-called time crystals. Here we investigate different kinds of partial temporal ordering, stabilized by non-periodic yet structured drives, which we call the rondeau order. Using carbon-13 nuclear spins in diamond as a quantum simulator, we use microwave driving fields to create tunable short-time disorder in a system exhibiting long-time stroboscopic order. Our spin control architecture allows us to implement a family of driving fields including periodic, aperiodic and structured random drives. We use a high-throughput read-out scheme to continuously observe the spin polarization and its rondeau order, with controllable lifetimes exceeding 4s. Using degrees of freedom associated with the short-time temporal disorder of rondeau order, we demonstrate the capacity to encode information in the response of observables. Our work broadens the landscape of observed non-equilibrium temporal order, and raises the prospect for the potential applications of driven quantum matter.

DOI: 10.1038/s41567-025-03028-y

Source: https://www.nature.com/articles/s41567-025-03028-y