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 and Al0.25Ga0.75As 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 annealed at 750°C for 30 s is relatively broadband and approaches 60% for dc electric fields of only 1.5×104 V/cm.