arXiv:cond-mat/0205319 · Physical Review A

Magnetism in a lattice of spinor Bose-Einstein condensates

Kevin A. Gross, Christopher P. Search, Han Pu, Weiping Zhang, Pierre Meystre

Published Sep 6, 2002• 38 citations

Abstract

We study the ground-state magnetic properties of ferromagnetic spinor Bose-Einstein condensates confined in deep optical lattices. In the Mott-insulator regime, the ``minicondensates'' at each lattice site behave as mesoscopic spin magnets that can interact with neighboring sites through both the static magnetic dipolar interaction and the light-induced dipolar interaction. We show that such an array of spin magnets can undergo a ferromagnetic or antiferromagnetic phase transition under the magnetic dipolar interaction depending on the dimension of the confining optical lattice. The ground-state spin configurations and related magnetic properties are investigated in detail.

DOI: 10.1103/physreva.66.033603

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