论文标题
定期驱动的非型物体多体旋转系统中的细能层
Prethermalization in periodically-driven nonreciprocal many-body spin systems
论文作者
论文摘要
我们分析了相互作用的混乱经典自旋系统中新的一类时周期非偏置动力学，其运动方程是保守的（具有相位空间 - 量），但没有符号结构。结果，系统的动力学不能来自任何依赖时间的哈密顿量。在高频极限中，我们发现磁化动力学具有长寿命的亚稳态，其持续时间由驱动频率的第四功率控制。但是，由于缺乏有效的哈密顿量，在规范合奏的框架内无法理解该系统进化为的高端状态。我们建议使用辅助自由度对系统进行哈密顿式扩展，其中原始旋转构成了一个开放但非解剖的子系统。这使我们能够扰动地得出有效的运动方程，该方程明显地显示出在反频率下以领先顺序破裂的符合性。因此，我们将在周期性驱动系统的高频极限中观察到的pr素动力学的概念扩展到了非注册系统。
We analyze a new class of time-periodic nonreciprocal dynamics in interacting chaotic classical spin systems, whose equations of motion are conservative (phase-space-volume-preserving) yet possess no symplectic structure. As a result, the dynamics of the system cannot be derived from any time-dependent Hamiltonian. In the high-frequency limit, we find that the magnetization dynamics features a long-lived metastable plateau, whose duration is controlled by the fourth power of the drive frequency. However, due to the lack of an effective Hamiltonian, the prethermal state the system evolves into cannot be understood within the framework of the canonical ensemble. We propose a Hamiltonian extension of the system using auxiliary degrees of freedom, in which the original spins constitute an open yet nondissipative subsystem. This allows us to perturbatively derive effective equations of motion that manifestly display symplecticity breaking at leading order in the inverse frequency. We thus extend the notion of prethermal dynamics, observed in the high-frequency limit of periodically-driven systems, to nonreciprocal systems.
