热环境下超量子失协的动力学特性
Dynamic Characteristics of Super Quantum Discord in Thermal Environment
摘要: 本文基于弱测量理论，给出了两个孤立原子在各自热库中的量子失协的动力学，分析量子失协与超量子失协随时间演化过程中的差异性，以及影响动力学演化的因素。我们发现，量子关联取决于人们对量子系统的扰动程度，标准量子失协和弱测量引起的超量子失协的差异随着测量强度参数的减小而增大。这意味着弱测量可以捕获更多的两体系统的量子失协。我们的结果表明，在其中一个子系统上执行的弱测量可以导致超量子失协，这是比投影测量捕获的标准量子失协更自然的量子关联测量。
Abstract: Based on the weak measurement theory, this paper gives the dynamics of quantum discord be-tween two isolated atoms in their respective thermal reservoirs, and analyzes the differences be-tween quantum discord and superquantum discord in the evolution process with time, as well as the factors affecting the dynamic evolution. We find that quantum correlation depends on the dis-turbance degree of quantum system, and the difference between standard quantum discord and super quantum discord caused by weak measurement increases with the decrease of measurement intensity parameter. This means that weak measurement can capture more quantum discord of two-qubit systems. Our results show that the weak measurement performed on one of the subsystems can lead to super quantum discord, which is a more natural quantum correlation measurement than the standard quantum discord captured by projection measurement.
文章引用：白梅, 徐鸿嘉, 闫学群. 热环境下超量子失协的动力学特性[J]. 现代物理, 2020, 10(6): 131-139. https://doi.org/10.12677/MP.2020.106015

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