We examine the dynamics of entanglement entropy of all parts in an open system consisting of a two-level dimer interacting with an environment of oscillators. The dimer-environment interaction is almost energy conserving. We find the precise link between decoherence and production of entanglement entropy. We show that not all environment oscillators carry significant entanglement entropy and we identify the oscillator frequency regions which contribute to the production of entanglement entropy. For energy conserving dimer-environment interactions the models are explicitly solvable and our results hold for all dimer-environment coupling strengths. We carry out a mathematically rigorous perturbation theory around the energy conserving situation in the presence of small non-energy conserving interactions.

中文翻译：

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通过退相干产生纠缠熵

我们检查了开放系统中所有部分的纠缠熵动力学，该系统由与振荡器环境相互作用的两级二聚体组成。二聚体与环境的相互作用几乎是能量守恒的。我们找到了退相干和纠缠熵产生之间的精确联系。我们表明，并非所有环境振荡器都带有显着的纠缠熵，并且我们确定了有助于产生纠缠熵的振荡器频率区域。对于节能二聚体-环境相互作用，模型是明确可解的，我们的结果适用于所有二聚体-环境耦合强度。在存在小的非能量守恒相互作用的情况下，我们围绕能量守恒情况进行了数学上严格的扰动理论。