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arXiv · 0812.4387

Generalized Purity and Quantum Phase Transition for Bose-Einstein condensates in a Symmetric Double Well

Thiago F. Viscondi·K. Furuya·M. C. de Oliveira
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Abstract

The generalized purity is employed for investigating the process of coherence loss and delocalization of the Q-function in the Bloch sphere of a two-mode Bose-Einstein condensate in a symmetrical double well with cross-collision. Quantum phase transition of the model is signaled by the generalized purity as a function of an appropriate parameter of the Hamiltonian and the number of particles (N). A power law dependence of the critical parameter with N is derived.

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Thiago F. Viscondi, K. Furuya, M. C. de Oliveira. 2008-12-23. Generalized Purity and Quantum Phase Transition for Bose-Einstein condensates in a Symmetric Double Well. https://doi.org/10.1103/physreva.80.013610

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