HAL : in2p3-00566419, version 1
 arXiv : 1004.2513
 Third Bose Fugacity Coefficient in One Dimension, as a Function of Asymptotic Quantities
 (2010)
 In one of the very few exact quantum mechanical calculations of fugacity coefficients, Dodd and Gibbs (\textit{J. Math.Phys}.,\textbf{15}, 41 (1974)) obtained $b_{2}$ and $b_{3}$ for a one dimensional Bose gas, subject to repulsive delta-function interactions, by direct integration of the wave functions. For $b_{2}$, we have shown (\textit{Mol. Phys}.,\textbf{103}, 1301 (2005)) that Dodd and Gibbs' result can be obtained from a phase shift formalism, if one also includes the contribution of oscillating terms, usually contributing only in 1 dimension. Now, we develop an exact expression for $b_{3}-b_{3}^{0}$ (where $b_{3}^{0}$ is the free particle fugacity coefficient) in terms of sums and differences of 3-body eigenphase shifts. Further, we show that if we obtain these eigenphase shifts in a distorted-Born approximation, then, to first order, we reproduce the leading low temperature behaviour, obtained from an expansion of the two-fold integral of Dodd and Gibbs. The contributions of the oscillating terms cancel. The formalism that we propose is not limited to one dimension, but seeks to provide a general method to obtain virial coefficients, fugacity coefficients, in terms of asymptotic quantities. The exact one dimensional results allow us to confirm the validity of our approach in this domain.
 Thème(s) : Physique/Matière Condensée/Gaz QuantiquesPhysique/Matière Condensée/Mécanique statistiquePhysique/Physique/Chimie-Physique
 Lien vers le texte intégral : http://fr.arXiv.org/abs/1004.2513
 in2p3-00566419, version 1 http://hal.in2p3.fr/in2p3-00566419 oai:hal.in2p3.fr:in2p3-00566419 Contributeur : Sophie Heurteau <> Soumis le : Mercredi 16 Février 2011, 10:46:31 Dernière modification le : Jeudi 17 Février 2011, 07:46:36