Equilibrium states of generic quantum systems subject to periodic driving.
Equilibrium states of generic quantum systems subject to periodic driving.
复制标题
DOI：
10.1103/physreve.90.012110
复制
发表时间：
2014-03
期刊：
影响因子：
--
通讯作者：
A. Lazarides;Arnab Das;R. Moessner
中科院分区：
文献类型：
--
作者：
A. Lazarides;Arnab Das;R. Moessner
当一个封闭的量子系统以周期T周期性地被驱动时，它会接近一个与驱动同步的周期状态，在这个周期状态中，任何频闪测量的局部可观测值都接近一个稳定值。对于可积系统，由此产生的行为被捕获的广义吉布斯系综的周期性版本。相比之下，在这里，我们表明，对于一般的不可积相互作用系统，局部可观的初始状态变得完全独立。本质上，这是因为受驱动系统在准能ω（α）处的Floquet本征态由非驱动哈密顿量的指数级多个本征态的混合组成，因此这些本征态是从整个广泛的非驱动谱中提取的。这是一种平衡形式，它只依赖于非驱动系统的希尔伯特空间，而不依赖于其哈密顿量的任何细节。
When a closed quantum system is driven periodically with period T, it approaches a periodic state synchronized with the drive in which any local observable measured stroboscopically approaches a steady value. For integrable systems, the resulting behavior is captured by a periodic version of a generalized Gibbs ensemble. By contrast, here we show that for generic nonintegrable interacting systems, local observables become independent of the initial state entirely. Essentially, this happens because Floquet eigenstates of the driven system at quasienergy ω(α) consist of a mixture of the exponentially many eigenstates of the undriven Hamiltonian, which are thus drawn from the entire extensive undriven spectrum. This is a form of equilibration which depends only on the Hilbert space of the undriven system and not on any details of its Hamiltonian.