Quantum magnetism of ultracold atoms with a dynamical pseudospin degree of freedom

Tobias Graß; Alessio Celi; Maciej Lewenstein

doi:10.1103/physreva.90.043628

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arXiv · 1401.7608

Quantum magnetism of ultracold atoms with a dynamical pseudospin degree of freedom

Tobias Graß·Alessio Celi·Maciej Lewenstein

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Abstract

We consider bosons in a Hubbard lattice with an SU($\cal N$) pseudospin degree of freedom which is made dynamical via a coherent transfer term. It is shown that, in the basis which diagonalizes the pseudospin coupling, a generic hopping process affects the spin state, similar to a spin-orbit coupling. This results, for the system in the Mott phase, in a ferromagnetic phase with variable quantization axis. In extreme cases, it can even give rise to antiferromagnetic order.

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Tobias Graß, Alessio Celi, Maciej Lewenstein. 2014-01-29. Quantum magnetism of ultracold atoms with a dynamical pseudospin degree of freedom. https://doi.org/10.1103/physreva.90.043628

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