High-power and high-uniform wide-waveguide DFB laser array assisted with phase compensators.

We propose and experimentally demonstrate a 16-wavelength high-power DFB laser array (HPLA) with phase compensators and 200 GHz spacing for optical I/O technologies. The grating of the proposed HPLA is fabricated using the reconstruction equivalent chirp (REC) technique to simplify the grating fabrication and enhance the precise control of the wavelength. The AR and HR films were coated on the front and rear facets of the laser to increase output power. The Ti-Pt heaters are integrated near the rear facet as the phase compensator to adjust the rear facet phase to improve the single-mode yield and achieve precise control of the lasing wavelength. Besides, the slab-coupled optical waveguide (SCOW) is utilized to improve the output power, reduce the differential resistance, as well as reduce the far-field divergence angle. The experimental results show that the 16-wavelength HPLA achieves precise wavelength control and excellent single-mode characteristics by adjusting the rear facet phase through the phase compensator. The fitted deviations of all the wavelengths are below 0.09 nm. The SMSRs of all wavelengths exceed 50 dB. At a bias current of 600 mA, the kink-free output power is greater than 100 mW, with a maximum differential resistance of 0.46 Ω. The slope efficiencies (SE) of all 16 lasers are above 0.25 W/A, and the power conversion efficiencies (PCE) are above 12% at the 100 mW output power. The measured Lorentzian linewidth and far-field FWHM divergence angle are 273.5 kHz and 11.3°×21.5°, respectively. The super performance of the proposed HPLA enables it to be used as a multi-wavelength source in optical I/O systems.