The temperature dependence of the recombination processes in 1.3 μm GaInNAs-based edge emitting lasers

The devices used in this study are various 1.3 μm GaInNAs (SQW and MQW) edge-emitting lasers (broad area and ridged), grown by solid source MBE and MOVPE. We determined I_th by measuring the light emitted from the facet and, using an optical fibre and an optical spectrum analyser (OSA). We also monitored the light emitted from a window milled in the n-contact of the laser. In this configuration, the collected spontaneous emission from the window will not have undergone any significant amplification or absorption, hence the integrated pure spontaneous emission rate L_sp is directly proportional to the radiative current I_rad. Studies of the spontaneous emission rate indicate that its temperature dependence around room temperature is well behaved with a characteristic temperature T_o(I_rad ) ~ 300 K at room temperature. Since T_o(I_th) is significantly less than T_o(I_rad) we can conclude that further temperature sensitive recombination processes must be present in these devices