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arXiv · 1101.5639

Pairing, Ferromagnetism, and Condensation of a normal spin-1 Bose gas

Stefan S. Natu·Erich J. Mueller
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Abstract

We theoretically study the stability of a normal, spin disordered, homogenous spin-1 Bose gas against ferromagnetism, pairing, and condensation through a Random Phase Approximation which includes exchange (RPA-X). Repulsive spin-independent interactions stabilize the normal state against both ferromagnetism and pairing, and for typical interaction strengths leads to a direct transition from an unordered normal state to a fully ordered single particle condensate. Atoms with much larger spin-dependent interaction may experience a transition to a ferromagnetic normal state or a paired superfluid, but, within the RPA-X, there is no instability towards a normal state with spontaneous nematic order. We analyze the role of the quadratic Zeeman effect and finite system size.

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Stefan S. Natu, Erich J. Mueller. 2011-01-28. Pairing, Ferromagnetism, and Condensation of a normal spin-1 Bose gas. https://doi.org/10.1103/physreva.84.053625

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