Drastic reduction of series resistance in doped semiconductor distributed Bragg reflectors for surface-emitting lasers

Abstract

Modifications to reduce the series resistance in p‐type semiconductor distributed Bragg reflectors (DBR) consisting of ten pairs of quarter‐wavelength GaAs (high refractive index)/Al_0.7Ga_0.3As (low index) layers were made by inserting an intermediate Al_0.35Ga_0.65As layer or a 200 Å superlattice of GaAs(10 Å)/Al_0.7Ga_0.3As (10 Å) at the GaAs/Al_0.7Ga_0.3As heterointerfaces. The specific DBR series resistance was reduced by two orders of magnitude to about 6.2×10⁻⁵ Ω cm². These modifications did not alter the optical reflectivity and nearly identical reflection spectra were measured.