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Quantum Spin Nematic States in Bose-Einstein Condensates

Fei Zhou
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Abstract

We review some recent results on discrete symmetries and topological order in spinor Bose-Einstein condensates (BECs) of $^{23}Na$. For spin one bosons with two-body scatterings dominated by a total spin equal to two channel, the BECs are in quantum spin nematic states at a low density limit. We study spin correlations in condensates at different limits and analyze hidde$ symmetries using a non-perturbative approach developed recently. We further more investigate the influence of hidden $Z_2$ symmetries and U(1) quantum orders in symmetry partially retored states, particularly the effects on topological excitations.

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Fei Zhou. 2002-12-19. Quantum Spin Nematic States in Bose-Einstein Condensates. https://doi.org/10.1142/s0217979203018399

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