Determination of the temperature and thermal resistance of a half-disk laser diode by measuring pulsed current-voltage characteristics

A technique is proposed for determining the temperature of a laser diode operating in a continuous mode, as well as thermal resistance of the device by comparing its current-voltage characteristic with pulsed current-voltage characteristics measured at different temperatures. The technique was applied to a $\varnothing$200 $\mu$m half-disk microlaser with an active region based on InGaAs/GaAs quantum dots. It was found that at currents corresponding to the peak laser power and lasing quenching due to overheating of the active region, the device temperature reaches 101 and 149$^\circ$C, respectively. The thermal resistance of the laser is 110 K/W.