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arXiv · 1106.0575

Collective modes of a strongly interacting Bose gas: probing the Mott transition

Michiel Snoek
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Abstract

We analyze the collective modes of a harmonically trapped, strongly interacting Bose gas in an optical lattice in the vicinity of the Mott insulator transition. For that aim we employ the dynamical Gutzwiller equations, by performing real-time evolution and by solving the equations in linear response. We find a strong dependence on the spatial dimension of the system: while in one dimension the frequency of the dipole mode vanishes at the Mott transition, in higher dimensions the dominant dipole mode is featureless and we find a signature only in the breathing mode. We discuss implications for experiments with bosonic and fermionic atoms.

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Michiel Snoek. 2012-04-26. Collective modes of a strongly interacting Bose gas: probing the Mott transition. https://doi.org/10.1103/physreva.85.013635

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