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Matter X waves

Claudio Conti·Stefano Trillo
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Abstract

We predict that an ultra-cold Bose gas in an optical lattice can give rise to a new form of condensation, namely matter X waves. These are non-spreading 3D wave-packets which reflect the symmetry of the Laplacian with a negative effective mass along the lattice direction, and are allowed to exist in the absence of any trapping potential even in the limit of non-interacting atoms. This result has also strong implications for optical propagation in periodic structures

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Claudio Conti, Stefano Trillo. 2003-08-13. Matter X waves. https://doi.org/10.1103/physrevlett.92.120404

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