Performance and reliability of widely tunable laser diodes

Abstract

We are manufacturing widely tunable laser diodes based on an integrated single chip design. The sampled-grating distributed Bragg reflector (SG-DBR) laser is monolithically integrated with a semiconductor optical amplifier (SOA). The continuous wave (cw) output power of the fully packaged device is more than 2OmW over the entire C-band with low noise figures and a high side-mode suppression ratio of over 40dB. Devices are made for L-band operation as well. The devices are well suited for long-haul and ultra-long-haul DWDM optical transport systems. For metro type applications we developed an EML-type device with a SG-DBR widely tunable laser monolithically integrated with an SOA and an electro-absorption modulator (EAM) based on the Franz-Keldysh effect. The operating speed is 2.7GbiVs for OC-48 systems including forward error correction (FEC). The time averaged output power is in excess of 5dBm over the 4Onm C-hand tuning range. The extinction ratio is larger than IOdJ3:Error free transmission over more than 350km of standard single mode fiber is demonstrated. Wavelength switching is accomblished in less than lOms which is limited by the control electronics. The monolithically integrated widely tunable SG-DBR lasers show excellent reliability and environmental stability results. After testings hundreds of devices over several thousands of hours a long wear-out lifetime of over 350 years has been inferred with a very low failure rate of less than IOOFITs over the normal operating lifetime. The results indicate no reliability penalty for wavelength tunability compared to standard fixed wavelength DFB lasers.