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arXiv · 0707.4444

Bose-Einstein Condensates in Strongly Disordered Traps

T. Nattermann·V. L. Pokrovsky
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Abstract

A Bose-Einstein condensate in an external potential consisting of a superposition of a harmonic and a random potential is considered theoretically. From a semi-quantitative analysis we find the size, shape and excitation energy as a function of the disorder strength. For positive scattering length and sufficiently strong disorder the condensate decays into fragments each of the size of the Larkin length ${\cal L}$. This state is stable over a large range of particle numbers. The frequency of the breathing mode scales as $1/{\cal L}^2$. For negative scattering length a condensate of size ${\cal L}$ may exist as a metastable state. These finding are generalized to anisotropic traps.

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BibTeXRIS

T. Nattermann, V. L. Pokrovsky. 2007-07-30. Bose-Einstein Condensates in Strongly Disordered Traps. https://doi.org/10.1103/physrevlett.100.060402

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