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arXiv · 1104.2512

Two component Bose-Hubbard model with higher angular momentum states

Abstract

We study a Bose-Hubbard Hamiltonian of ultracold two component gas of spinor Chromium atoms. Dipolar interactions of magnetic moments while tuned resonantly by ultralow magnetic field can lead to spin flipping. Due to approximate axial symmetry of individual lattice site, total angular momentum is conserved. Therefore, all changes of the spin are accompanied by the appearance of the angular orbital momentum. This way excited Wannier states with non vanishing angular orbital momentum can be created. Resonant dipolar coupling of the two component Bose gas introduces additional degree of control of the system, and leads to a variety of different stable phases. The phase diagram for small number of particles is discussed.

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J. Pietraszewicz, T. Sowinski, M. Brewczyk, J. Zakrzewski, M. Lewenstein, M. Gajda. 2012-05-09. Two component Bose-Hubbard model with higher angular momentum states. https://doi.org/10.1103/physreva.85.053638

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