论文标题
浮力动力学量子相变于周期性淬火系统
Floquet dynamical quantum phase transitions in periodically quenched systems
论文作者
论文摘要
动力学量子相变（DQPT）的特征是物理可观察到时间的非分析行为。当系统受时间周期调制的约束时，其可观察物的非分析特征可能会及时重复出现，从而导致Floquet dqpt的现象。在这项工作中，我们系统地探索了一类带有手性对称性的定期淬火的一维系统中的floquet dqpts。通过调整淬火的强度，我们在单个驾驶期内发现了多个浮点数DQPT，当系统在具有较大拓扑不变的较大拓扑的floquet状态下初始化系统时，会观察到更多的DQPT。每个Floquet DQPT进一步伴随着动态拓扑顺序参数的量化跳跃，如果在间隙的拓扑阶段制备了基础浮雕系统，则其值会及时量化。该理论在分段淬灭的晶格模型中得到了证明，该模型具有丰富的浮光拓扑阶段，并且可以在量子模拟器中很容易实现，例如钻石中的氮化中心。因此，我们的发现为DQPTS的浮雕工程和Floquet Systems中拓扑相变的动态检测提供了新的视角。
Dynamical quantum phase transitions (DQPTs) are characterized by nonanalytic behaviors of physical observables as functions of time. When a system is subject to time-periodic modulations, the nonanalytic signatures of its observables could recur periodically in time, leading to the phenomena of Floquet DQPTs. In this work, we systematically explore Floquet DQPTs in a class of periodically quenched one-dimensional system with chiral symmetry. By tuning the strength of quench, we find multiple Floquet DQPTs within a single driving period, with more DQPTs being observed when the system is initialized in Floquet states with larger topological invariants. Each Floquet DQPT is further accompanied by the quantized jump of a dynamical topological order parameter, whose values remain quantized in time if the underlying Floquet system is prepared in a gapped topological phase. The theory is demonstrated in a piecewise quenched lattice model, which possesses rich Floquet topological phases and is readily realizable in quantum simulators like the nitrogen-vacancy center in diamonds. Our discoveries thus open a new perspective for the Floquet engineering of DQPTs and the dynamical detection of topological phase transitions in Floquet systems.
