Observation of femtosecond coherent midinfrared emission in asymmetric quantum wells

Summary form only given. Here, we make use of the coherent charge oscillation in an asymmetric quantum well after excitation by a 15-fsec optical pulse, to produce mid-infrared radiation. As shown the bandwidth of such a short pulse is large enough to excite a wave packet consisting of a coherent superposition of states El and E2 of the asymmetric quantum well.