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arXiv · 1108.2768

Quantum phase transition of two-mode Bose-Einstein condensates with an entanglement order parameter

Wei Fan·Yan Xu. Bing Chen·Zhaoyang Chen·Xunli Feng·C. H. Oh
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Abstract

The ground state entanglement of the two-mode Bose-Einstein condensate is investigated through a quantum phase transition approach. The entanglement measure is taken as the order parameter and this is a non-local order parameter, which is different from the conventional order parameter of the Mott insulator-superfluid phase transitions. For this non-local order parameter, scaling behavior corresponding to a continuous phase transition is obtained and a power-law divergence near the critical region follows it. This scaling behavior of quantum entanglement is analyzed by the finite-size scaling and the critical exponents are obtained as $ν= 1.01$ and $γ= 0.86$. A close connection between quantum fluctuations and the phase transition of entanglement is also obtained.

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Wei Fan, Yan Xu. Bing Chen, Zhaoyang Chen, Xunli Feng, C. H. Oh. 2012-01-19. Quantum phase transition of two-mode Bose-Einstein condensates with an entanglement order parameter. https://doi.org/10.1103/physreva.85.013645

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