Laser pulse amplification and dispersion compensation in an effectively extended optical cavity containing Bose–Einstein condensates

Abstract

We review and critically evaluate our proposal of a pulse amplification scheme based on two Bose–Einstein condensates inside the resonator of a mode-locked laser. Two condensates are used for compensating the group velocity dispersion. Ultraslow light propagation through the condensate leads to a considerable increase in the cavity round-trip delay time, lowers the effective repetition rate of the laser, and hence scales up the output pulse energy. It has been argued recently that atom–atom interactions would make our proposal even more efficient. However, neither in our original proposal nor in the case of interactions, were limitations due to heating of the condensates by optical energy absorption taken into account. Our results show that there is a critical time of operation, 0.3 ms, for the optimal amplification factor, which is of the order of ∼102 at effective condensate lengths of the order of ∼50 μm. The bandwidth limitation of the amplifier on the minimum temporal width of the pulse that can be amplified with this technique is also discussed.