Condensed Matter Physics, 2009, vol. 12, No. 4, pp. 559571
DOI:10.5488/CMP.12.4.559
Title:
Bose condensation in (random) traps
Author(s):

Th. Jaeck
(School of Mathematical Sciences, University College Dublin Belfield, Dublin 4, Ireland)
,


J.V. Pulé
(School of Mathematical Sciences, University College Dublin Belfield, Dublin 4, Ireland)
,


V.A. Zagrebnov
(Université de la Méditerranée (AixMarseille II), Centre de Physique Théorique  UMR 6207 CNRS, Luminy  Case 907, 13288 Marseille, Cedex 09, France)

We study a noninteracting (perfect) Bosegas in random external potentials (traps). It is shown that a generalized BoseEinstein condensation in the random eigenstates manifests if and only if the same occurs in the oneparticle kineticenergy eigenstates, which corresponds to the generalized condensation of the free Bosegas. Moreover, we prove that the amounts of both condensate densities are equal. This statement is relevant for justification of the Bogoliubov approximation} in the theory of disordered boson systems.
Key words:
generalized BoseEinstein condensation, random potentials, integrated density of states, Lifshitz tails
PACS:
05.30.Jp, 03.75.Fi, 67.40.w
