Theory for a Hanbury Brown Twiss experiment with a ballistically expanding cloud of cold atoms

José Carlos Viana Gomes (1, 2) , Aurélien Perrin (2) , Martijn Schellekens (2) , Denis Boiron (2) , Christoph I Westbrook (2) , Michael Belsley (1)

1 Departamento de Fisica [Braga]
2 laboratoire Charles Fabry de l'Institut d'Optique / Optique atomique

We have studied one-body and two-body correlation functions in a ballistically expanding, non-interacting atomic cloud in the presence of gravity. We find that the correlation functions are equivalent to those at thermal equilibrium in the trap with an appropriate rescaling of the coordinates. We derive simple expressions for the correlation lengths and give some physical interpretations. Finally a simple model to take into account finite detector resolution is discussed.

Mots clés: fonction de corrélation à deux corps; condensat de Bose-Einstein

Domaines: Physique Quantique [quant-ph]; Autre [cond-mat.other]; Optique [physics.optics]

José Carlos Viana Gomes, Aurélien Perrin, Martijn Schellekens, Denis Boiron, Christoph I Westbrook, et al.. Theory for a Hanbury Brown Twiss experiment with a ballistically expanding cloud of cold atoms. Physical Review A : Atomic, molecular, and optical physics [1990-2015], 2006, 74, pp.053607. ⟨10.1103/PhysRevA.74.053607⟩. ⟨hal-00080649v2⟩