Entanglement swapping for two pairs of EPR eigenstates generated via Bell measurement

摘要

We demonstrate that a common eigenvector eta] (Einstein, Podolsky and Rosen, EPR states) of two particles' relatively coordinate and total momentum possesses a property that the projection (a Bell measurement) of two pairs of EPR states eta](1,2) x eta'](3,4) onto the subspace spanned by 1,4[eta", yields a EPR state eta" - eta* - eta'*](2,3) for particles 2 and 3. Entanglement swapping operator is also derived by virtue of the technique of integration within an ordered product of operators. [References: 23]