2001/05/31 by A. Yu. Cherny, A. A. Shanenko
Physics and Astronomy · #cond-mat.stat-mech
paper · pdf · doi:10.1016/s0375-9601(02)00017-8
published as Phys. Lett. A 293, No 5-6, 287 (2002). · 5 pages, REVTeX, 1 figure inserted
arxiv created 2001/11/30 · arxiv updated 2009/11/30
The kinetic and interaction energies of a three-dimensional dilute ground-state Bose gas confined in a trap are calculated beyond a mean-field treatment. They are found to depend on the pairwise interaction trough two characteristic lengths: the first, a, is the well-known scattering length and the second, b, is related to the latter by b=a-λd a/dλwith λbeing the coupling constant. Numerical estimations show that the pairwise interaction energy of a dilute gas of alkali atoms in a trap is negative (in spite of the positive scattering length); its absolute value is found by about the order of magnitude larger than that of the mean-field interaction energy that corresponds to the last term in the Gross-Pitaevskii functional.