25-Gb/s Multichannel 1.3- $\mu$m Surface-Emitting Lens-Integrated DFB Laser Arrays

Two multichannel 1.3-μ m lens integrated surface-emitting laser arrays for massive data links were fabricated. The basic structure of the lasers consists of a short InGaAlAs multiple-quantum-well distributed-feedback (DFB) active-stripe array monolithically integrated with both a 45° total reflection mirror and an aspheric collimation lens. One of them, a four-channel laser array based on this structure, exhibited clear 25-Gb/s eye openings up to 50°C over all four channels and achieved a total output of 100 Gb/s. The other laser, a multiple-wavelength array for wavelength-division-multiplexing applications, produces multiple-wavelength emission thanks to precisely modified DFB gratings by electron beam lithography. It exhibited nine-wavelength stable single-mode operation (side-mode suppression ratio >; 40 dB) between 1260 and 1290 nm at 3.7-nm intervals, and a clear 25-Gb/s eye opening for each wavelength. These two surface-emitting laser arrays have demonstrated their suitability for next-generation multichannel data links (including 100-Gb Ethernet and optical interconnects).