Tight, robust, and feasible quantum speed limits for open dynamics
Tight, robust, and feasible quantum speed limits for open dynamics
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DOI：
10.22331/q-2019-08-05-168
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发表时间：
2018-06
期刊：
影响因子：
6.4
通讯作者：
Francesco Campaioli;F. A. Pollock;K. Modi
中科院分区：
文献类型：
--
作者：
Francesco Campaioli;F. A. Pollock;K. Modi
从几何的角度出发，我们推导出任意开放量子演化的量子速度极限，它可以是马尔可夫或非马尔可夫的，为最一般的量子动力学所需的时间提供了一个基本的界限。我们的方法依赖于测量表示为广义布洛赫向量的（混合）状态之间的角度和距离。我们研究我们的边界的性质，并提出其形式为封闭和开放的进化，后者在林德布拉德形式和内存内核。我们的速度限制是可证明的组合和混合下，功能，大大提高了量子速度限制的有效性，为开放的混合状态的演变。我们还证明，我们的界限是更容易计算和测量比其他量子速度限制的开放演化，它是严格的比以前的界限几乎所有的开放过程。最后，我们讨论了量子速度限制的有用性及其在当前研究中的影响。
Starting from a geometric perspective, we derive a quantum speed limit for arbitrary open quantum evolution, which could be Markovian or non-Markovian, providing a fundamental bound on the time taken for the most general quantum dynamics. Our methods rely on measuring angles and distances between (mixed) states represented as generalized Bloch vectors. We study the properties of our bound and present its form for closed and open evolution, with the latter in both Lindblad form and in terms of a memory kernel. Our speed limit is provably robust under composition and mixing, features that largely improve the effectiveness of quantum speed limits for open evolution of mixed states. We also demonstrate that our bound is easier to compute and measure than other quantum speed limits for open evolution, and that it is tighter than the previous bounds for almost all open processes. Finally, we discuss the usefulness of quantum speed limits and their impact in current research.