Luminescence of GaAs/AlGaAs asymmetric double-quantum-wells excited by a mid-IR free electron laser

Luminescence has been observed from a GaAs/AlGaAs asymmetric double-quantum-wells (ADQWs) structure when excited by intense mid-infrared (IR) radiation from a free-electron laser (FEL). The intensity of the luminescence is found to depend strongly on the mid-IR FEL average power, while the dependence on temperature is quite weak compared to that of photoluminescence excited by a He-Ne laser. The experimental results also show that the peak energy of the luminescence is almost independent of the external applied voltage. However, the detailed mechanism for the luminescence induced by the intense mid-IR radiation only remains unidentified in the present study. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)