PHOTON-ECHO IN SEMICONDUCTORS - A STOCHASTIC APPROACH

Femtosecond photon echos in semiconductors are studied on the basis of a stochastic description of the polarization decay. A satisfactory agreement with experimental results [Phys. Rev. Lett. 61, 1647 (1988)] is found with respect to the nonexponential decay of the echo energy as a function of the time delay between the laser pulses. Moreover, the shape of the echo is studied, and the detuning of the laser frequency with respect to the band edge is found to depend significantly on the shape of the light pulses.