title: Interaction effects on number fluctuations in a Bose-Einstein condensate of light.
abstract: We investigate the effect of interactions on condensate-number fluctuations in Bose-Einstein condensates. For a contact interaction we variationally obtain the equilibrium probability distribution for the number of particles in the condensate. To facilitate comparison with experiment, we also calculate the zero-time delay autocorrelation function g((2))(0) for different strengths of the interaction. Finally, we focus on the case of a condensate of photons and find good agreement with recent experiments.
authors.affiliation: Institute for Theoretical Physics and Center for Extreme Matter and Emergent Phenomena, Utrecht University, Leuvenlaan 4, 3584 CE Utrecht, The Netherlands.
authors.forename: E C I
authors.initials: EC
authors.lastname: van der Wurff
authors.affiliation: Institute for Theoretical Physics and Center for Extreme Matter and Emergent Phenomena, Utrecht University, Leuvenlaan 4, 3584 CE Utrecht, The Netherlands.
authors.forename: A-W
authors.initials: AW
authors.lastname: de Leeuw
authors.affiliation: Institute for Theoretical Physics and Center for Extreme Matter and Emergent Phenomena, Utrecht University, Leuvenlaan 4, 3584 CE Utrecht, The Netherlands.
authors.forename: R A
authors.initials: RA
authors.lastname: Duine
authors.affiliation: Institute for Theoretical Physics and Center for Extreme Matter and Emergent Phenomena, Utrecht University, Leuvenlaan 4, 3584 CE Utrecht, The Netherlands.
authors.forename: H T C
authors.initials: HT
authors.lastname: Stoof