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Two-mode entanglement in two-component Bose-Einstein condensates

H. T. Ng·P. T. Leung
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Abstract

We study the generation of two-mode entanglement in a two-component Bose-Einstein condensate trapped in a double-well potential. By applying the Holstein-Primakoff transformation, we show that the problem is exactly solvable as long as the number of excitations due to atom-atom interactions remains low. In particular, the condensate constitutes a symmetric Gaussian system, thereby enabling its entanglement of formation to be measured directly by the fluctuations in the quadratures of the two constituent components [Giedke {\it et al.}, Phys. Rev. Lett. {\bf 91}, 107901 (2003)]. We discover that significant two-mode squeezing occurs in the condensate if the interspecies interaction is sufficiently strong, which leads to strong entanglement between the two components.

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H. T. Ng, P. T. Leung. 2004-05-20. Two-mode entanglement in two-component Bose-Einstein condensates. https://doi.org/10.1103/physreva.71.013601

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