Reflectivity and photoluminescence studies in Bragg reflectors with absorbing layers

Reflectivity and photoluminescence studies on the GaAs/AIAs Bragg mirror with the InGaAs/InGaAsP multiple quantum well absorbing cover layer were performed at a wavelength of 1550 nm. An absorption dip enhanced by optical confinement of the Fabry-Perot resonance was observed in the reflectivity spectra. The refractive indexes of the AlAs/GaAs quarter-wave stacks and cover layer were obtained by tuning the angle of incidence tin reflectivity) and angle of detection (in photoluminescence) in the Bragg reflector, respectively. The photoluminescence studies also provide a vehicle for obtaining the absorption coefficient of the cavity medium by measuring the quality factor of the Fabry-Perot mode.