Change in band configuration of In0.57Ga0.43As1-xSbx/AlAs0.48Sb0.52 quantum wells from type-II to type-I by increasing Sb composition x

InGaAs/AIAsSb systems lattice matched to InP have two distinguishable features: a high conduction band offset and type-II band configuration. Although, the former results in a large intersubband transition (ISBT) at conduction band, the latter makes it difficult to use the effective interband transition (IBT). To overcome this latter problem, the effect of the Sb was investigated because Sb would act as a band modulator from type-II to type-I. In0.57Ga0.43As1-xSbx/AlAs0.48Sb0.52 single quantum well (SQW) samples with various Sb compositions x, were grown on GaAs substrates via AlAS(0.48)Sb(0.52) buffer layer. Their photoluminescence (PL) properties were examined to identify their band configurations. When the excitation laser power was increased, the PL property of In0.57Ga0.43As SQW sample, showed a larger blue shift than that of In0.57Ga0.43As1-xSbx (x >= 0.13) ones. This indicates that the band configuration modulates from type-II to type-I when the antimonide composition is larger than 0.13. These findings indicate that new functional devices can be fabricated using a combination of IBT and ISBT. (c) 2006 Elsevier B.V. All rights reserved.