Effect of Asi on the optical properties of Ga1−xInxAs/InP grown by molecular beam epitaxy

Abstract

This report focuses on the effect of the As species and the V III ratio on the optical properties of Ga 1− x In x As/InP grown by molecular beam epitaxy (MBE). The band gap energies of the layers were measured by low temperature photoluminescence (PL) while the indium contents x were determined by X-ray for samples in the investigated range of0.50 < × < 0.56. For the analysis of these data we considered the model of Kuo et al. which we confined with a correction for the different measurement temperatures in PL (4.2 K) and X-ray (300 K). Using As 4 with an effective V III ratio higher than 1.3, we find the best agreement of the band gap energies and predictions of the theory. A lower V III ratio always implies a reduction of the band gap energy to values 5–15 meV lower than expected. In contrast, using As 2 the PL data fit quite well independent of the effective V III ratio above unity.