Optical investigation of modulation-doped In0.53Ga0.47As/In0.48Al0.52As multiple quantum well heterostructures

Abstract
We present the results of the first optical studies of modulation-doped In0.53Ga0.47As/ In0.48Al0.52As multiple quantum well heterostructures. By a combination of luminescence and absorption measurements, we have distinguished between intrinsic and extrinsic luminescence processes. We show that the intrinsic luminescence dominates above 70 K and results from recombination of two-dimensional electron plasma with photoexcited holes. Spectral line shape analysis yields important sample parameters. The use of As2 source appears to enhance the purity of the material as compared to the material grown with As4 source.