AI 中文总结
研究周期性驱动自旋系统中多体周期轨道，发现远离稳定周期轨道的扰动类似准粒子能带结构，通过能带工程实现双可调预热化，建立了稳定非平衡相的途径及周期轨道与多体混沌间的概念桥梁。
AI 中文摘要
我们在远离高频极限的周期性驱动（弗洛凯）自旋系统中发现了一族多体周期轨道。线性稳定性分析预测受扰多体轨迹会保持靠近稳定周期轨道，但热力学原理表明弗洛凯加热最终会出现。我们的工作旨在解决这两种预期之间的矛盾。具体而言，我们表明远离稳定周期轨道的扰动具有类似于准粒子能带结构的描述。当无隙点附近的模式被缓慢填充时，会出现一个长寿命的预热阶段。色散决定预热寿命，我们展示了能带工程如何导致预热寿命\(R^{-W}\)的“双可调”参数依赖性，其中\(R\)是准粒子分布在动量空间的宽度，\(W\)是无隙点附近色散的指数。我们的结果不仅为稳定驱动多体系统中的非平衡物质相建立了一条有力途径，还在“低维”非线性系统中的周期轨道与多体混沌之间建立了概念上的桥梁。
英文摘要
We uncover a family of many-body periodic orbits in a periodically driven (Floquet) spin system away from the high-frequency limit. While linear stability analysis predicts that perturbed many-body trajectories remain close to stable periodic orbits, thermodynamic principles dictate that Floquet heating will ultimately set in. Our work aims to resolve the tension between these two expectations. In particular, we show that perturbations away from the stable periodic orbits feature a description akin to a quasiparticle band structure. A long-lived prethermal regime appears when modes around the gapless point are slowly populated. The dispersion determines the prethermal lifetime, and we show how band engineering leads to a "doubly tunable" parametric dependence of the prethermal lifetime $R^{-W}$, with $R$ the width in momentum space of the quasiparticle distribution and $W$ the exponent of the dispersion around the gapless point. Our results not only establish a powerful route toward stabilizing non-equilibrium phases of matter in driven many-body systems but also establish a conceptual bridge between periodic orbits in 'low-dimensional' nonlinear systems and many-body chaos.
