Entanglement Concentration of Entangled Squeezed Vacuum States
Xinhua Cai, Kuang Le-Man · Chinese Physics Letters · 2002
By analysing the action of a beamsplitter on squeezed vacuum states (SVSs), it is found that, if the two input light beams of the beamsplitter have the same squeezing amplitude and phase, the output state is a two-mode SVS. If the two input light beams of the beamsplitter have the same squeezing amplitude but a phase difference of π, the output state is a direct product state of two single-mode SVSs. Based on these results, we propose to distill a maximally entangled SVS from a partially entangled SVS by using a 50/50 beamsplitter and photodetectors.