Unifying Quantum and Classical Speed Limits on Observables
Unifying Quantum and Classical Speed Limits on Observables
复制标题
DOI：
10.1103/physrevx.12.011038
复制
发表时间：
2022-02-28
影响因子：
12.5
通讯作者：
Gorshkov, Alexey, V
中科院分区：
文献类型：
--
作者：
Garcia-Pintos, Luis Pedro;Nicholson, Schuyler B.;Gorshkov, Alexey, V
噪声的存在或与环境的相互作用可以从根本上改变原本孤立的量子系统的可观测到的动力学。我们得到了开放量子系统可观测性演化速度的一个界限。将这一速度极限分为Mandelstam和Tamm最初的时间-能量测不准关系和最近针对经典系统导出的时间-信息测不准关系，并将其推广到开放量子系统。通过分离对系统动力学的相干和非相干贡献，我们得到了演化速度的下界和上界。我们证明了后者提供了比先前已知的量子速度限制更严格的对可观测的速度的限制，并且速度算符的优选基用来完全描述饱和速度限制的可观测的特征。我们使用这种结构来限制非相干动力学对可观测演化的影响，并找到给可观测演化带来最大相干加速比的哈密顿量。
The presence of noise or the interaction with an environment can radically change the dynamics of observables of an otherwise isolated quantum system. We derive a bound on the speed with which observables of open quantum systems evolve. This speed limit is divided into Mandelstam and Tamm's original time-energy uncertainty relation and a time-information uncertainty relation recently derived for classical systems, and both are generalized to open quantum systems. By isolating the coherent and incoherent contributions to the system dynamics, we derive both lower and upper bounds on the speed of evolution. We prove that the latter provide tighter limits on the speed of observables than previously known quantum speed limits and that a preferred basis of speed operators serves to completely characterize the observables that saturate the speed limits. We use this construction to bound the effect of incoherent dynamics on the evolution of an observable and to find the Hamiltonian that gives the maximum coherent speedup to the evolution of an observable.