Long-wavelength InP-based quantum-dash lasers

Self-assembled InAs quantum-dash (QD) lasers with emission wavelengths between 1.54 and 1.78 mum based on the AlGaInAs-AIInAs-InP material system were grown by gas source molecular beam epitaxy. Threshold current densities below 1 kA/cm(2) were achieved for 1-mm-long mirror coated broad area lasers with a stack of four QD layers. The devices can be operated up to 80 degreesC in pulsed mode and show a high T-0 value of 84 K up to 35 degreesC. In comparison to quantum-well lasers a much lower temperature sensitivity of the emission wavelength was achieved. The temperature shift of Deltalambda/DeltaT = 0.12 nm/K is as low as that caused by the refractive index change.