论文标题
有界的光锥和稳健的拓扑顺序从平衡
Bounded light cone and robust topological order out of equilibrium
论文作者
论文摘要
拓扑有序的大汉尔顿人的基态退化是自我校正量子记忆的基岩，不幸的是，即使在零温度下，它们也不会远离平衡。由于零温度下的稳定性是有限温度鲁棒性的先决条件，因此这种瘟疫阻止了实用的鲁棒自我纠正。在这项工作中，我们表明，有界光锥的出现使统一的时间演变成为准绝热延续，从而保留了拓扑顺序，而初始地面空间始终保持其宏观距离，以作为量子代码。我们还展示了有限的光锥如何通过Kitaev的曲折代码和蜂窝模型中的合适扰动出现。我们的结果表明，在零温度下，拓扑顺序和自我校正量子记忆可以动态稳定。
The ground state degeneracy of topologically ordered gapped Hamiltonians is the bedrock for self-correcting quantum memories, which are unfortunately not stable away from equilibrium even at zero temperature. This plague precludes practical robust self-correction since stability at zero temperature is a prerequisite for finite-temperature robustness. In this work, we show that the emergence of a bounded light cone renders the unitary time evolution a quasi-adiabatic continuation that preserves topological order, with the initial ground space retaining its macroscopic distance at all times as a quantum code. We also show how bounded light cones can emerge through suitable perturbations in Kitaev's toric code and honeycomb model. Our results suggest that topological orders and self-correcting quantum memories can be dynamically robust at zero temperature.
