On-chip single-output InAs quantum dot DFB laser for photonic integration.

We present monolithically integrated InAs-QD DFB lasers incorporating a high-reflectivity multi-mode interference reflector (MMIR) for single-facet emission. The fabricated devices achieve over 6 mW single-mode laser output at room temperature, with a side-mode suppression ratio (SMSR) over 50 dB. Furthermore, control of the lasing mode and power is demonstrated by carrier injection to the MMIR section. This includes deliberate switching from multi-mode to single mode operation and lasing-wavelength selection at either side of the DFB stopband. A power attenuation, with extinction ratio (ER) over 50 dB is achieved for single-mode lasing as the MMIR section current injection is increased by <3 mA.