Pressure-induced Γ-<i>X</i> crossover in the conduction band of ordered and disordered GaInP alloys

Abstract

Pressure-dependent photoluminescence in both ordered and disordered Ga0.5In0.5P is reported. In ordered Ga0.5In0.5P, emissions are observed from both the direct band gap at the Brillouin zone center (Γ) and from the indirect band gap involving the conduction band at the X point of the Brillouin zone. The conduction-band minima at X and Γ in the ordered phase are found to be lowered in energy by the same amount with respect to those in the disordered phase. Our results support the existence of ordering along the [001] direction in GaInP as proposed recently by Kurtz.