Fundamental limits on quantum dynamics based on entropy change
Fundamental limits on quantum dynamics based on entropy change
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DOI：
10.1063/1.4997044
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发表时间：
2018-01-01
影响因子：
1.3
通讯作者：
Wilde, Mark M.
中科院分区：
文献类型：
--
作者：
Das, Siddhartha;Khatri, Sumeet;Wilde, Mark M.
在量子力学和信息论领域，人们都知道单位物理过程的熵是不减的。然而，在一般情况下，熵不表现出单调的行为。这限制了熵变化在描述演化过程中的应用。最近，在布塞米、达斯和王尔德的工作中提供了熵变的下限[Phys. Rev. A 93（6），062314（2016）]。我们探讨的限制，这个限制的地方的物理演化的量子系统，并讨论如何将这些限制可以作为证人来表征量子动力学。特别是，我们推导出无记忆量子动力学的熵变率的下限，我们认为，它提供了一个见证的非么正性。熵变率的这个限制导致了在量子动力学中测试记忆效应的几个见证者的定义。此外，从上述熵变的下界，我们得到了单位演化的非么正性的一个度量。出版社：AIP Publishing
It is well known in the realm of quantum mechanics and information theory that the entropy is non-decreasing for the class of unital physical processes. However, in general, the entropy does not exhibit monotonic behavior. This has restricted the use of entropy change in characterizing evolution processes. Recently, a lower bound on the entropy change was provided in the work of Buscemi, Das, and Wilde [Phys. Rev. A 93(6), 062314 (2016)]. We explore the limit that this bound places on the physical evolution of a quantum system and discuss how these limits can be used as witnesses to characterize quantum dynamics. In particular, we derive a lower limit on the rate of entropy change for memoryless quantum dynamics, and we argue that it provides a witness of non-unitality. This limit on the rate of entropy change leads to definitions of several witnesses for testing memory effects in quantum dynamics. Furthermore, from the aforementioned lower bound on entropy change, we obtain a measure of non-unitarity for unital evolutions. Published by AIP Publishing.