Reduction of Electon-Phonon Scattering Rates by Total Spatial Quantization

Abstract

The physics of spatially quantized systems has been the subject of intense investigation since the introduction of MBE and MOCVD. Quantum wells have been exhaustively examined since the seminal works of Dingle et al[1]. More recently, studies on quantum wires[2] have yielded interesting new properties. Here, we present data on a completely spatial quantized system that shows unique photoluminescence structure resulting from an electron or hole phonon scattering bottleneck. This paper discloses evidence of the modification of carrier-phonon scattering rates by the imposition of complete spatial quantization on GaAs-AlGaAs quantum wells. The photoluminescence spectra exhibit striking structure in the normal intrinsic exciton luminescence of the confined quantum well states which is best explained by a bottleneck for electron/hole energy loss. We believe that this bottleneck is a direct consequence of the quantization of the electronic and/or phonon dispersion relations. This photoluminescence structure does not occur for samples of higher dimensionality.