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arXiv 1202.5532cond-mat.str-elcond-mat.dis-nn
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多体局域化模型中纠缠的无界增长

Unbounded growth of entanglement in models of many-body localization

Jens H. Bardarson, Frank Pollmann, Joel E. Moore

摘要:

一个重要而尚未完全回答的问题是,一个由许多相互作用粒子组成的封闭量子系统是否可以通过无序来定域。用数值方法研究了由无规场XXZ哈密顿量描述的一维无自旋费米子相互作用系统的简单(非纠缠)初态的时间演化。相互作用引起纠缠传播的剧烈变化和粒子传播的较小变化。即使是弱相互作用,当系统被认为是在一个多体局域相,纠缠既不显示本地化也不扩散的行为,但在一个无限的系统中的增长没有限制:相互作用作为一个奇异的扰动没有相互作用的本地化状态。对原子实验的意义在于局域测量将显示出在多体定域态中的大而非热的熵。这种熵在一个发散的时间尺度上缓慢地(近似地)发展,就像在玻璃系统中一样。

英文摘要:

An important and incompletely answered question is whether a closed quantum system of many interacting particles can be localized by disorder. The time evolution of simple (unentangled) initial states is studied numerically for a system of interacting spinless fermions in one dimension described by the random-field XXZ Hamiltonian. Interactions induce a dramatic change in the propagation of entanglement and a smaller change in the propagation of particles. For even weak interactions, when the system is thought to be in a many-body localized phase, entanglement shows neither localized nor diffusive behavior but grows without limit in an infinite system: interactions act as a singular perturbation on the localized state with no interactions. The significance for proposed atomic experiments is that local measurements will show a large but nonthermal entropy in the many-body localized state. This entropy develops slowly (approximately logarithmically) over a diverging time scale as in glassy systems.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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