The semiclassical and quantum regimes of super-radiant light scattering from a Bose-Einstein condensate

We show that many features of the recent experiments of Schneble et al (2003 Science 300 475), which demonstrate two different regimes of light scattering by a Bose-Einstein condensate, can be described using a one-dimensional mean-field quantum CARL model, where optical amplification occurs simultaneously with the production of a periodic density modulation in the atomic medium. The two regimes of light scattering observed in these experiments, originally described as 'Kapiza-Dirac scattering' and 'super-radiant Rayleigh scattering', can be interpreted as the semiclassical and quantum limits respectively of CARL lasing.