AI 中文总结
研究有限维系统热平衡态经突然淬火后的动态量子相变，基于准厄米框架构建混合态洛施密特振幅推导有限温度淬火动力学，应用于N能级模型发现温度通过热权重分布控制相变，有维度相关阈值温度，此机制为控制动态临界性提供原理。
AI 中文摘要
我们研究了处于热平衡态并经历突然淬火的有限维系统中的动态量子相变（DQPTs）。在一个度量平稳的伪厄米框架内，从第一原理构建了混合态洛施密特振幅，给出了有限温度淬火动力学的自洽推导。将此框架应用于一个由与N - 2个旁观态耦合的两能级部分组成的N能级模型，发现温度通过本征态间热权重的重新分布来控制DQPTs。该机制导致一个与维度相关的阈值温度，当希尔伯特空间维度达到五时变为有限值，高于此值洛施密特振幅失去所有实零点且DQPTs被完全抑制。热抑制机制提出了通过热占据控制动态临界性的一般原理，而准厄米框架为其严格推导提供了自洽基础。
英文摘要
We investigate dynamical quantum phase transitions (DQPTs) in finite-dimensional systems prepared in thermal equilibrium states and subjected to a sudden quench. A mixed-state Loschmidt amplitude is constructed from first principles within a metric-stationary pseudo-Hermitian framework, providing a self-contained derivation of the finite-temperature quench dynamics. Applying this framework to an $N$-level model consisting of a two-level sector coupled to $N-2$ spectator states, we find that temperature controls the DQPTs through the redistribution of thermal weights among the eigenstates. This mechanism leads to a dimensionality-dependent threshold temperature that becomes finite when the Hilbert-space dimension reaches five, above which the Loschmidt amplitude loses all real zeros and the DQPTs are fully suppressed. The thermal suppression mechanism suggests a general principle for controlling dynamical criticality through thermal occupation, while the quasi-Hermitian framework provides the self-consistent foundation for its rigorous derivation.
