Photoluminescence decay characteristics of an oxide-confined vertical-cavity surface-emitting laser

Room temperature time-resolved photoluminescence (TRPL) decay measurements are performed on oxidized and unoxidized vertical-cavity surface-emitting lasers (VCSELs). The oxidized device shows faster photoluminescence (PL) decay time (370ps) compared to the unoxidized device (1200ps). The oxidation of the AlAs layers reduces the aperture area and causes a blueshift in the cavity resonance wavelength, relative to that of the unoxidized device. The faster decay time can be attributed to better optical field confinement inside the microcavity which results in an increase in the transition probability of electron-hole recombination.