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arXiv · 0712.0431

Spontaneous rotation in one-dimensional systems of cold atoms

Akiyuki Tokuno·Masahiro Sato
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Abstract

We theoretically study harmonically trapped one-dimensional Bose gases (e.g., Li, Na, K, Rb, etc.) with multibands occupied, focusing on effects of higher-energy bands. Combining the Ginzburg-Landau theory with the bosonization techniques, we predict that the repulsive interaction between higher-band bosons and the quantum fluctuation can induce the ground state with a finite angular momentum around the trapped axis. In this state, the Z_2 reflection symmetry (clockwise or anticlockwise rotations) is spontaneously broken.

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Akiyuki Tokuno, Masahiro Sato. 2008-07-22. Spontaneous rotation in one-dimensional systems of cold atoms. https://doi.org/10.1103/physreva.78.013623

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