A Novel High Speed Directly Modulated Dual Wavelength 1.3 μm DFB Laser for THz Communications

We report a novel high speed directly modulated dual wavelength 1.3 μm laser for THz communication applications. The laser has a compact size and simple structure, which consists a DFB section and a passive distributed Bragg reflector (DBR) section, leading to a device fabrication procedure similar to that of a normal DFB laser. The laser has an over 26 GHz modulation bandwidth in the dual wavelength working mode, which facilitates high speed data modulation onto THz wave. NRZ data modulations at up to 50 Gb/s have been demonstrated successfully. The bit error rate (BER) performances under 10 and 25 Gb/s NRZ data modulation are studied. 10 ⁻¹⁰ BER can be obtained and the 10 km fiber transmission power penalty when compared with the back to back transmissions is less than 0.5 dB. This device is a low-cost but powerful light source for future photonics based high speed THz communication system.