arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2008.11764quant-phmath-phmath.MP
收藏

矩阵乘积态的广义Rényi熵

Extensive Rényi entropies in matrix product states

Alberto Rolandi, Henrik Wilming

摘要:

我们证明了由一般的(带隙的)平移不变矩阵乘积态(MPS)描述的自旋链的所有Rényi纠缠熵对于不连通子系统是可拓的:由每个第k个自旋组成的子系统的所有Rényi纠缠熵密度在热力学极限下是非零的当且仅当该状态在热力学极限下不收敛到乘积态.此外,我们还根据MPS的转移算子的展开系数及其标准型不动点的谱性质,给出了纠缠熵的明确下界。作为副结果,我们得到了本原量子信道的膨胀系数和奇异值分布的一个下界。对于单位量子信道,这产生了一个非常简单的下限的奇异值的分布和膨胀系数的克劳斯秩。物理上,我们的研究结果的动机是在多体局域系统,我们审查的平衡问题。

英文摘要:

We prove that all Rényi entanglement entropies of spin-chains described by generic (gapped), translational invariant matrix product states (MPS) are extensive for disconnected sub-systems: All Rényi entanglement entropy densities of the sub-system consisting of every k-th spin are non-zero in the thermodynamic limit if and only if the state does not converge to a product state in the thermodynamic limit. Furthermore, we provide explicit lower bounds to the entanglement entropy in terms of the expansion coefficient of the transfer operator of the MPS and spectral properties of its fixed point in canonical form. As side-result we obtain a lower bound for the expansion coefficient and singular value distribution of a primitve quantum channel in terms of its Kraus-rank and entropic properties of its fixed-point. For unital quantum channels this yields a very simple lower bound on the distribution of singular values and the expansion coefficient in terms of the Kraus-rank. Physically, our results are motivated by questions about equilibration in many-body localized systems, which we review.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑