Long wavelength vertical-cavity semiconductor optical amplifiers

This paper overviews the properties and possible applications of long wavel ength vertical-cavity semiconductor optical amplifiers (VCSOAs), A VCSOA op erating in the 1.3-mum wavelength region is presented. The device was fabri cated using wafer bonding; it was optically pumped and operated in reflecti on mode. The reflectivity of the VCSOA top mirror was varied in the charact erization of the device. Results are presented for 13 and 12 top mirror per iods. By reducing the top mirror reflectivity, the amplifier gain, optical bandwidth, and saturation output power were simultaneously improved. For th e case of 12 top mirror periods, we demonstrate 13-dB fiber-to-fiber gain, 0.6 nm (100 GHz) optical bandwidth, a saturation output power of -3.5 dBm a nd a noise figure of 8.3 dB, The switching properties of the VCSOA are also briefly investigated. By modulating the pump laser, we have obtained a 46- dB extinction ratio in the output power, with the maximum output power corr esponding to 7-dB fiber-to-fiber gain. All results are for continuous wave operation at room temperature.