摘要
In(Phys Lett A,2002,297:4-8) an entanglement criterion for finite-dimensional bipartite systems is proposed:If ρ AB is a separable state,then Tr(ρA2) Tr(ρ2) and Tr(ρB2) Tr(ρ2).In the present paper this criterion is extended to infinite-dimensional bipartite and multipartite systems.The reduction criterion presented in(Phys Rev A,1999,59:4206-4216) is also generalized to infinitedimensional case.Then it is shown that the former criterion is weaker than the later one.
In （Phys Lett A, 2002, 297： 4-8） an entanglement criterion for finite-dimensional bipartite systems is proposed： IfpAB is a separable state, then Tr（PZA） 〉/ Tr（ρ2） and Tr（ρB2） 〉/ Tr（p2）. In the present paper this criterion is extended to infinite-dimensional bipartite and multipartite systems. The reduction criterion presented in （Phys Rev A, 1999, 59： 4206--4216） is also generalized to infinitedimensional case. Then it is shown that the former criterion is weaker than the later one.
基金
supported by the National Natural Science Foundation of China (11171249)
the Natural Science Foundation of Shanxi Province (2011021002-2)
