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arXiv · 1112.0837

Quantum entangled ground states of two spinor Bose-Einstein condensates

Z. F. Xu·R. Lü·L. You
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Abstract

We revisit in detail the non-mean-field ground-state phase diagram for a binary mixture of spin-1 Bose-Einstein condensates including quantum fluctuations. The non-commuting terms in the spin-dependent Hamiltonian under single spatial mode approximation make it difficult to obtain exact eigenstates. Utilizing the spin z-component conservation and the total spin angular momentum conservation, we numerically derive the information of the building blocks and evaluate von Neumann entropy to quantify the ground states. The mean-field phase boundaries are found to remain largely intact, yet the ground states show fragmented and entangled behaviors within large parameter spaces of interspecies spin-exchange and singlet-pairing interactions.

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Z. F. Xu, R. Lü, L. You. 2011-12-05. Quantum entangled ground states of two spinor Bose-Einstein condensates. https://doi.org/10.1103/physreva.84.063634

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