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arXiv:1103.5790 · Physical Review A

Phase transitions in dipolar spin- 1 Bose gases

Ville Pietilä, Mikko Möttönen

Published Jul 15, 2011• 2 citations
arXivHTMLPDF

Abstract

We study phase transitions in homogeneous spin-$1$ Bose gases in the presence of long-range magnetic dipole--dipole interactions (DDI). We concentrate on three-dimensional (3D) geometries and employ momentum shell renormalization group to study the possible instabilities caused by the DDI. At the zero-temperature limit where quantum fluctuations prevail, we find the phase diagram to be unaffected by the DDI. When the thermal fluctuations dominate, polar and ferromagnetic condensates with DDI become unstable and we discuss this crossover in detail. On the other hand, the spin-singlet condensate remains stable in the presence of DDI.

DOI
10.1103/physreva.84.013605

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We study phase transitions in homogeneous spin-111 Bose gases in the presence of long-range magnetic dipole--dipole interactions (DDI). We concentrate on three-dimensional (3D) geometries and employ momentum shell renormalization group to study the possible instabilities caused by the DDI. At the zero-temperature limit where quantum fluctuations prevail, we find the phase diagram to be unaffected by the DDI. When the thermal fluctuations dominate, polar and ferromagnetic condensates with DDI become unstable and we discuss this crossover in detail. On the other hand, the spin-singlet condensate remains stable in the presence of DDI.
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