论文标题
离散时间晶体的激发激发
An instanton-like excitation of a discrete time crystal
论文作者
论文摘要
自发的对称性断裂和基本激发是彼此密切相关的凝结物理学的两个支柱。对称性及其自发破坏不仅控制基本激发的动力学和光谱，还决定了它们的基本结构。在本文中，我们研究了非平衡量子问题的激发特性：一种自发打破时间翻译对称性的离散时间晶体相。结果表明，这种有趣的对称性破裂允许激发激发，代表两个“退化”时间晶体相之间的隧道。此外，我们还观察到一个动力学过渡点，即插入“大小”分歧，对临界统计统计学物理学中的关键降低现象的回忆。已经提出了一种现象学理论来了解所提出系统的相动态，并还讨论了实验性的实现和检测。
Spontaneous symmetry breaking and elementary excitation are two of the pillars of condensed matter physics that are closely related to each other. The symmetry and its spontaneous breaking not only control the dynamics and spectrum of elementary excitations, but also determine their underlying structures. In this paper, we study the excitation properties of a non-equilibrium quantum matter: a discrete time crystal phase that spontaneously breaks the temporal translational symmetry. It is shown that such an intriguing symmetry breaking allows an instanton-like excitation that represents a tunneling between two "degenerate" time crystal phases. Furthermore, we also observe a dynamical transition point at which the instanton "size" diverges, a reminiscence of the critical slowing down phenomenon in nonequilibrium statistic physics. A phenomenological theory has been proposed to understand the phase dynamics of the proposed system and the experimental realization and detection have also been discussed.
