Physics of Low-Dimensional Ultracold Bose Gases

Christopher James Foster

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arXiv · 1302.0470

Physics of Low-Dimensional Ultracold Bose Gases

Christopher James Foster

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Abstract

In this work we investigate the unique properties of ultracold Bose gases in one and two dimensions. In two dimensions, we present simulations of the Berezinskii-Kosterlitz-Thouless (BKT) phase transition using the projected Gross-Pitaevskii equation formalism. We confirm the presence of the BKT phase by observing algebraic decay in the first-order correlation function, unbinding of vortex pairs, and behaviour of the superfluid fraction. In one dimension we use a transverse Gaussian ansatz and the Lagrangian approach to derive an effective equation of motion for the one dimensional Bose gas at zero temperature.

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Christopher James Foster. 2013-02-03. Physics of Low-Dimensional Ultracold Bose Gases. https://arxiv.org/abs/1302.0470

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