Long-wavelength quantum dot FP and DFB lasers for high temperature applications

High temperature (>125°C) resistant long-wavelength semiconductor lasers are attractive as light sources in a variety of harsh environments. Here, we report extremely high temperature continuous-wave (CW) operation of QD lasers on GaAs substrate emitted at 1300-nm-range by enhancing gain and increasing the quantized-energy separation of the QD active layers. A suppression of the In out-diffusion during MBE from self-assembled InAs QDs significantly reduced inhomogeneous broadening with high QD sheet density maintained. QD-FP laser exhibited record high CW-lasing temperature for long-wavelength laser of 220°C and QD-DFB laser also exhibited high CW-lasing temperature of 150°C by employing high gain QD active media.