High Modulated Output Power Over 9.0 dBm With 1570-nm Wavelength SOA Assisted Extended Reach EADFB Laser (AXEL)

Abstract

With a view to realizing a light source for future access networks, we demonstrated a 1570-nm (L-band) wavelength semiconductor optical amplifier (SOA) assisted extended reach electroabsorption-modulater integrated with a distributed feedback (EADFB) laser (AXEL) for a high modulated light output power ( P avg) of more than 9.0 dBm. We first compared the static lasing characteristics of the AXEL with those of a conventional EADFB laser fabricated on the same wafer. We found that the light output power of the AXEL was significantly higher and the power conversion efficiency of the AXEL was more than double that of the EADFB laser. Second, we experimentally estimated the effect of the integrated SOA. Under typical driving conditions, a net SOA gain of 4.9 dB was obtained, and the excellent chirp compensation effect of the SOA was observed. Next, we investigated the AXEL driving condition in terms of power conversion efficiency and found that the AXEL with commonly driven laser diode and SOA sections approached the most efficient driving condition even when the electroabsorption modulator bias voltage was applied. Finally, the 10-Gbit/s transmission characteristic was examined. A sufficient P avg of 9.0 dBm was achieved, revealing the potential for access network applications. Furthermore, the transmission distance was successfully extended to 80 km thanks to the chirp compensation effect of the SOA.