All electrical laser diode characterization by monolithic integration with a photodiode

The combination of a laser diode integrated on top of a photodiode has been shown to be of interest as an electronic device for optoelectronic circuits (the photon transport transistor) and for reducing the power dissipation of a laser at thresholds up to 42% through photon recycling. The added photodiode also proves to be a powerful analysis tool for determining laser parameters, characterizing mirror processing, and studying laser diode degradation. Without a single optical measurement one can determine the laser threshold current, the nonradiative lifetime of the carriers, and the differential quantum efficiency. Early degradation of the laser diode was also studied by monitoring the light absorbed in the photodiode.