Entanglement Swapping for Distant Bose-Einstein Condensates

Libo Chen, Chunhong Zheng, Hongyang Ma +1 more

Yu Bo Shi

Cao Yong-zheng, Kuang Le-Man

We propose a scheme of entanglement swapping and concentration in a system consisting of multi-pair entangled trapped Bose–Einstein condensates (BECs). In this scheme, entanglement swapping is accomplished by using interference-pattern joint measurements and detecting the total number of condensed atoms leaking out of relevant traps while entanglement concentration is realized by controlling inter-atomic nonlinear and tunnelling interactions. Three- and four-pair BEC schemes are investigated in detail. It is found that with the increasing number of the entangled pairs, the region of entanglement concentration is broadened and the amount of concentrated entanglement is enhanced.

Ji-Bing Yuan, Bo Zhang

We propose a potentially practical scheme to entangle two distant atomic Bose-Einstein condensates (BEC), which is respectively in an optical cavity. Due to interaction between the cavity and the atomic BEC and the cavity decay, a linear polarized single-photon, which inputs the cavity, will rotate a certain angle after the input-output process, which is called Faraday rotation. Thanks to the faraday rotation of the photonic polarization, through detecting the output photonic polarization, we will entangle two distant Bose-Einstein condensates and generate entangled coherent states. Therefore, we provide a possible way to realize long-distance macroscopic quantum entanglement.

Heide Narnhofer

Anders Søndberg Sørensen, L.-M. Duan, J. I. Cirac +1 more