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Bose-Einstein condensation in the presence of a uniform field and a point-like impurity

R. M. Cavalcanti·P. Giacconi·G. Pupillo·R. Soldati
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Abstract

The behavior of an ideal $D$-dimensional boson gas in the presence of a uniform gravitational field is analyzed. It is explicitly shown that, contrarily to an old standing folklore, the three-dimensional gas does not undergo Bose-Einstein condensation at finite temperature. On the other hand, Bose-Einstein condensation occurs at $T\neq 0$ for $D=1,2,3$ if there is a point-like impurity at the bottom of the vessel containing the gas.

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R. M. Cavalcanti, P. Giacconi, G. Pupillo, R. Soldati. 2002-02-22. Bose-Einstein condensation in the presence of a uniform field and a point-like impurity. https://doi.org/10.1103/physreva.65.053606

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