Design and characterization of 200-mW-class distributed feedback lasers at 1.55 /spl mu/m

High-power 1.55-/spl mu/m distributed feedback lasers for radio-frequency applications have been designed, fabricated and characterized. By employing a broadened-waveguide design in a distributed feedback laser, continuous-wave single-mode performance up to 220 mW has been successfully demonstrated at a heat-sink temperature of -15/spl deg/C. The average external differential quantum efficiency was 31% over the entire operating range. Single-mode power levels of 162 mW were observed at 15/spl deg/C. Linewidths of 750 kHz and 1 MHz were measured at power levels of 73 mW and 114 mW, respectively. The relative intensity noise was measurement-limited at a value of -165 dB/Hz at 1 GHz for a power level of 114 mW.