A high power amplitude modulated laser of carrier frequency ω1 and modulation frequency Ω propagating through a semiconductor exerts a ponderomotive force on electrons at Ω. When Ω∼ωp/εL (ωp being the plasma frequency and εL the lattice permittivity), the ponderomotive force produces a large amplitude plasma wave. The free carrier density fluctuations associated with the plasma wave are also large, particularly when the laser has forward and backward propagating components. Another laser of frequency ω2 propagating through this region couples with the free carrier density oscillations to produce sidebands at ω2±Ω. Thus the information contained in the first laser is transferred to the second laser. The scheme is effective when Ω is larger than the collision frequency.