Enhanced electro‐optic properties of low‐temperature‐growth GaAs and AlGaAs

The signal‐bandwidth products of excitonic electroabsorption of low‐temperature‐growth (LTG) molecular beam epitaxial films of GaAs:As and Al0.25Ga0.75As:As are larger than in the related stoichiometric materials. The enhanced electro‐optic properties of these composites may be caused by increased inhomogeneity of dc electric fields. The differential transmission in LTG Al0.25Ga0.75As:As annealed at 750 °C for 30 s is relatively broadband and approaches 60% for dc electric fields of only 1.5×104 V/cm.