Novel Technologies for 1.55µm Vertical Cavity Lasers

We report on three novel vertical-cavity laser (VCL) structures for 1.55-?m operation. Two of the structures utilize an n-type GalnAsP/ InP Bragg mirror combined with an Al(Ga)As/GaAs mirror using either wafer fusion or metamorphic epitaxial growth. The third employs two wafer-fused AlGaAs/GaAs mirrors, in which lateral current confinement is obtained by localized fusion of the p mirror. All three VCLs use strained GalnAsP quantum wells as active material and achieve continuous-wave (cw) operation at room temperature or above. The single fused VCL operates up to 17 and 101°C in continuous-wave and pulsed mode, respectively. The monolithic VCL-structure with a metamorphic GaAs/AlAs n-type mirror uses a reverse-biased tunnel junction for current injection. This laser achieves record high output power (1 mW) at room temperature and operates cw up to 45°C. The double fused VCLs with a 10x 10-?m2 active area operate cw up to 30°C with threshold current as low as 2.5 mA and series resistance of 30 H. The emission spectra exhibit a single lasing mode polarized with 30-dB extinction ratio and a spectral linewidth of 150 MHz.