中文摘要：

文章提出了一类纠缠目击者．它们是以局域正交可观测量的形式给出的，因而自动提供了利用局域测量和经典通信来探测纠缠的方法．利用Jamiolkowski同构得到了相应的非完全正的正映射，从而导出一类新的可分性判据——O-约化判据．约化判据和重排判据都是该判据的特例．另外，还发现O-约化判据可以通过测量局域正交可观测量的一个厄米关联矩阵来获得物理的实现．作为应用，构造了Horodecki在1997年发现的第一个束缚纠缠态的纠缠目击者的清晰形式，并且提出了一类d×d束缚纠缠态．其纠缠可以通过对局域正交可观测量进行置换来探测．

英文摘要：

We propose a family of entanglement witnesses. These witnesses are constructed by using local orthogonal observables, and therefore can be easily measured by means of local measurements and classical communications. From the Jamiolkowski isomorphism we obtain the corresponding positive maps that are not completely positive. These maps lead to a new separability criterion the O-reduction criterion, which includes the reduction criterion and the realignment criterion as special cases, in addition, we find that the O-reduction criterion can be physically realized by measuring a Hermitian correlation matrix of local orthogonal observables. As applications, we construct an explicit entanglement witness for the first bound entangled state found by Horodecki in 1997, and as well introduce a family of d×d bound entangled states, whose entanglement can be detected by permuting local orthogonal observables.