Evolution of Valence-Band Alignment with Nitrogen Content in GaNAs/GaAs Single Quantum Wells

Artikel i vetenskaplig tidskrift, 2008

We report on experimental evidence for the transition of valence-band alignment from type I to type II in Ga Nx As1-x GaAs single quantum wells by photoreflectance measurements. The substitutional nitrogen content covers a range of 1.4%-5.9%. The turning point of the type I-type II transition occurs at x4.7%. The experimental observations can be well interpreted by a combination of band anticrossing model and model-solid theory when nonlinear behavior of either the shear deformation potential or the average valence-band energy is taken into account. The effect of dilute nitrogen on the valence-band offset of GaNAsGaAs quantum well structure is hence clarified. © 2008 American Institute of Physics.