The energy gap of dilute nitride GaAsSbN has been studied. We found that the energy gap reduction induced by nitrogen incorporation is nearly independent of the Sb composition of the alloy, indicating that the conduction band and the valence band can be independently manipulated by incorporating N and Sb, respectively. A “double” band anticrossing (BAC) model, which is a combination of a BAC model for GaAsN and a valence BAC model for GaAsSb with the localized levels and hybridization parameters reported in literatures, has been proposed to fit the energy gap of annealed GaAsSbN samples. The as-grown samples, however, are with lower energy gaps, most likely resulting from the existence of substitutional N pairing and clustering in the alloys.

No abstract

Photoreflectance and photoluminescence investigations of a step-like Ga In N As Sb ∕ Ga As N ∕ Ga As quantum well tailored at 1.5 μ m : The energy level structure and the Stokes shift J. Appl. Phys. 97, 053515 (2005); 10.1063/1.1854729Large blueshift of the band gap of Ga As Sb ∕ Al Sb quantum wells with ion implantation

No abstract

Thermal annealing effects of a GaAs 0.909 Sb 0.07 N 0.021 film grown on GaAs substrate via gas-source molecular beam epitaxy have been characterized by photoluminescence ͑PL͒ and photoreflectance ͑PR͒ techniques. PL measurements show the evolution of luminescence feature with the thermal annealing treatment. The conduction to heavy-hole ͑HH͒ band and conduction to light-hole ͑LH͒ band transitions originated from the strained induced valence band splitting in GaAs 0.909 Sb 0.07 N 0.021 layer have been observed by the PR measurements. The near band edge transition energies are slightly blueshifted, and the splitting of HH and LH bands is reduced with rising annealing temperature. The temperature dependences of near band edge transition energies are analyzed using Varshni and Bose-Einstein expressions in the temperature range from 15 to 300 K. The parameters that describe the temperature variations of the near band edge transition energies are evaluated and discussed.