Entanglement Manipulation for a Two-Mode Squeezed Vacuum State
ZHOU Qing-Ping1,2,3, FANG Mao-Fa1,2, LIU Xiao-Juan1,2, CHEN Xiao-Mei1,2, WU Qin1
1Department of Physics, Hunan Normal University, Changsha 410081
2Anhui Institute Optics and Fine Mechanics, Chinese Academy of ScienceS, Hefei 230031
3Department of Mathematics and Computer Science, Jishou University, Zhangjiajie 427000
Entanglement Manipulation for a Two-Mode Squeezed Vacuum State
1Department of Physics, Hunan Normal University, Changsha 410081
2Anhui Institute Optics and Fine Mechanics, Chinese Academy of ScienceS, Hefei 230031
3Department of Mathematics and Computer Science, Jishou University, Zhangjiajie 427000
Abstract： By numerically analysing the entropy of entanglement of the output state from a Mach--Zehnder interferometer for the two-mode squeezed vacuum state input, it is found that if the internal phase shift of the interferometer is adjusted to the value of 0 or π, the entangling characteristic of the input state is efficiently preserved at the output. If the internal phase shift is tuned to the value of π, the two-mode squeezed vacuum state is completely disentangled at the output of the setup. If the internal phase shift deviates from the above values, the input state is degraded into a partially entangled output state. Based on these results, a method for optically realizing the entanglement preservation, entanglement degradation, and disentanglement via the interferometer is obtained.
2004, Vol. 21 
