Operation of a 25-Gbps Direct Modulation Ridge Waveguide MQW-DFB Laser up to 85 °C

We demonstrated 25-Gbps direct modulation up to 85 °C with a 1.3-μm InGaAlAs RWG-MQW-DFB laser. The dependence of the relaxation oscillation frequency on current was 3.3 GHz/mA½ and this is the highest value ever reported.