论文标题
凸线式纠缠密度矩阵块块对角线的密度矩阵的研究，用于研究热状态
Convex-roof entanglement measures of density matrices block diagonal in disjoint subspaces for the study of thermal states
论文作者
论文摘要
我们提供了一个证据，表明任何密度矩阵的纠缠，这些密度矩阵在子空间中阻塞对角线的任何密度矩阵在两个潜在的纠缠子系统之一的希尔伯特空间方面是不相交的，可以简单地计算为每个块中存在的纠缠的加权平均值。这对于始终继承了哈密顿量中存在的对称性的热平衡状态特别有用，因为块 - 二角形哈密顿量是常见的，而相互作用也仅涉及一个更大的系统的单一自由度。我们在简单的哈密顿量上举例说明了我们的方法，显示了可能在不同参数范围内出现的吉布斯状态纠缠可能温度依赖性的多样性。
We provide a proof that entanglement of any density matrix which block diagonal in subspaces which are disjoint in terms of the Hilbert space of one of the two potentially entangled subsystems can simply be calculated as the weighted average of entanglement present within each block. This is especially useful for thermal-equilibrium states which always inherit the symmetries present in the Hamiltonian, since block-diagonal Hamiltonians are common as are interactions which involve only a single degree of freedom of a greater system. We exemplify our method on a simple Hamiltonian, showing the diversity in possible temperature-dependencies of Gibbs state entanglement which can emerge in different parameter ranges.
