Observation of Small Temperature Variation of Longitudinal-Mode Peak Wavelength in TlInGaAs/InP Laser Diodes

To fabricate temperature-insensitive wavelength laser diodes (LDs), which are important in the wavelength division multiplexing optical fiber communication system, we have studied TlInGaAs/InP heterostructures. TlInGaAs/InP metal-stripe LDs were fabricated with gas source molecular-beam epitaxy. Current-injection pulsed-laser operation was obtained up to 310 K. Threshold current density and lasing wavelength at room temperature were 7 kA/cm2 and 1660 nm, respectively. The observed temperature variation of the longitudinal-mode peak wavelength was as small as 0.06 nm/K. This value is much smaller than that observed for distributed feed-back LDs (0.1 nm/K). This is considered to result from the addition of Tl into the LD active layer.