GaInAsP/InP surface emitting injection lasers with short cavity length

We have succeeded in making a surface emitting (SE) GaInAsP/InP injection laser with short cavity length (= 10 μm) which operates at 1.22 μm of wavelength with threshold current of 160 mA at 77 K. No side emitting mode was observed as a result of preparing long absorbing regions and a small dot electrode (20 μm φ). Only one longitudinal SE mode dominated up to 1.7 times the threshold and the far-field radiation angle was sharp (
2\Delta\theta \approx 10\deg
). Fabrication processes and lasing condition are detailed.