SPONTANEOUS EMISSION FACTOR OF OXIDIZED VERTICAL-CAVITY SURFACE-EMITTING LASERS FROM THE MEASURED BELOW-THRESHOLD CAVITY LOSS

A method to estimate the spontaneous emission factor beta is proposed and applied to the 780 nm oxidized vertical-cavity surface-emitting la sers. The proportionality of the measured cavity loss multiplied by op tical power to injected current is used. Our results agree better with theoretical calculations than those of conventional light-current cur ve fitting. The spontaneous emission factor of 0.0021 is obtained for a 2-mu m-square device at room temperature. Since only the below-thres hold information of cavity loss and output power are used in our metho d, the obtained beta values are independent of any complex and unexpec ted above-threshold effects such as thermally induced mode-size contra ction, as they should be. (C) 1997 American Institute of Physics.