关于两体量子态纠缠目击的一些注记

A note on the entanglement witness of bipartite quantum states

在回顾总结两体量子态纠缠目击已有结论的基础上,对两体量子态纠缠目击的一些定理进行了进一步的探讨.基于自伴算子的一种分解,给出了纠缠目击的一个刻画,证明了纠缠目击的一系列性质,并举例说明了两体量子态最优纠缠目击的判定.最后,给出了最优纠缠目击的若干性质,提出了最优不可分解纠缠目击的一种判定方法.

Based on the existing conclusions on entanglement wttness of bipartite states entanglement o witnesses of bipartite quantum states are further discussed. Firstly,in light of a decomposition of a self- adjoint operator, characterization of an entanglement witness is given, and some properties of entangle- ment witnesses are proved. An example is taken to illustrate the judgment of optimal entanglement wit- ness. Finally,the optimal entanglement witnesses are discussed and a judgment of optimal indecomposa- ble entanglement witness is presented.