Wideband tunable REC-DFB laser array using thin-film heaters on the submount

A wideband wavelength-tunable 4 × 5 distributed feedback (DFB) semiconductor laser array based on the reconstruction-equivalent-chirp (REC) technique using a simple tuning scheme is demonstrated. It consists of 20 DFB lasers with 4 × 5 matrix interleaving distributions, two-level cascaded Y-branch optical combiners, and one active semiconductor optical amplifier (SOA), all in-series integrated on one chip. Unlike the traditional thermal-electric cooler (TEC)-based wave-length-tuning scheme, the tunable 4 × 5 REC-DFB laser array achieves a faster and broader continuous wavelength-tuning range using TaN thin-film heaters integrated on the AlN submount. By changing the injection current of the TaN resistor from 0 to 190 mA, the proposed tunable laser achieves a wavelength-tuning range of ∼ 2.5 nm per channel and a total tuning of over 50 nm. This study opens up new avenues for realizing cost-effective and wide-tuning-range semiconductor lasers. capability is proposed and experimentally demonstrated. We present a 4 × 5 interleaving matrix-grating DFB-MLA fabricated with the reconstruction-equivalent-chirp (REC) technique and design a simple wavelength-tuning scheme by integrating thin-film heaters on the submount. Continuous wavelength tuning of over 50 nm is realized at a tuning speed of 10 nm/s.