Enhancement of collective atomic recoil lasing due to pump phase modulation

We investigate the effect of a phase-modulated pump beam on collective backscattering also termed collective atomic recoil lasing CARL by a cold, collisionless atomic gas. We show using a numerical analysis that different regimes can be identified in which the atomic dynamics evolves in a qualitatively different manner during the light-atom interaction, depending on the magnitude of the pump modulation frequency. Our results also demonstrate that phase-modulating the pump field can substantially enhance the backscattered field