Low Power, Low Cost, Long Wavelength VCSELs for Optical Interconnects

Vertical Cavity Surface-Emitting Lasers VCSELs will be important in large-scale optical interconnection schemes because of the ability to fabricate large arrays of devices at a low cost. Long wavelength VCSELs offer many performance advantages for optical interconnects compared to their shorter wavelength near-IR counterparts, including lower voltage and power. Until recently, it has not been feasible to fabricate long-wavelength 1300 nm VCSELs due to fundamental materials limitations in the InP based system. The first breakthrough in potentially realizing long wavelength VCSELs on GaAs substrates was the work on GaInNAs by Kondow, et al 1 Subsequently, M. Larson, working with Kondow demonstrated the first long wavelength optically pumped GaInNAs VCSEL 2 and electrically pumped VCSEL 3. The exciting potential of these lasers is fivefold 1 extension of VCSEL technology across the entire 1.3-1.6 micrometers communications band, 2 high temperature operation and high T0. 3 low power, 4 low cost and 5 monolithic integration with GaAs electronics. Seeing the tremendous potential for this new alloy material, we initiated a new effort at Stanford University to improve the performance of GaInNAs lasers to levels comparable to or better than shorter wavelength near-IR VCSELs. This report details the work of that effort which resulted in the first cw, room temperature GaInNAs VCSEL operating at 1.2 micrometers.