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arXiv 1508.01883quant-phcond-mat.mes-hallcond-mat.quant-gas
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Floquet Chern绝缘体的量子退火和非平衡动力学

Quantum annealing and non-equilibrium dynamics of Floquet Chern insulators

Lorenzo Privitera, Giuseppe E. Santoro

摘要:

通过时间周期微扰诱导拓扑转变为控制材料的性质提供了一条途径。在这里,我们表明,绝热制备的一个非平凡的状态涉及选择性人口的边缘状态,由于指数小的差距防止绝热。我们通过研究具有缓慢增加振幅的跳跃相位的石墨烯样带来说明这一点,例如,缓慢开启的圆偏振激光器。感应电流具有大的周期性振荡,但在时间平均时仅在边缘流动,并且可以通过将激光聚焦在任一边缘来控制。大块经历了一个非平衡的拓扑转变,由Bianco和Resta在平衡引入的本地陈标记的信号。的绝热图片中存在的带内共振的失败进行了讨论。

英文摘要:

Inducing topological transitions by a time-periodic perturbation offers a route to controlling the properties of materials. Here we show that the adiabatic preparation of a non-trivial state involves a selective population of edge-states, due to exponentially-small gaps preventing adiabaticity. We illustrate this by studying graphene-like ribbons with hopping's phases of slowly increasing amplitude, as for, e.g., a circularly polarized laser slowly turned-on. The induced currents have large periodic oscillations, but flow solely at the edges upon time-averaging, and can be controlled by focusing the laser on either edge. The bulk undergoes a non-equilibrium topological transition, as signaled by the local Chern marker introduced by Bianco & Resta in equilibrium. The failure of the adiabatic picture in presence of intraband resonances is discussed.

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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