Wideband continuously-tuned matrix DFB laser array assisted with enhanced self-heating effect based on REC technique

Abstract

In this letter, we propose and experimentally demonstrate a wideband continuously-tuned matrix distributed feedback (DFB) laser array. This DFB laser array is developed based on the reconstruction-equivalent-chirp (REC) technique and has an enhanced self-heating effect. The laser array is made up of 24 DFB lasers that are arranged in an 8 × 3 matrix interleaving pattern. Moreover, it integrates a three-level cascaded Y-branch optical combiners and an active semiconductor optical amplifier (SOA) on a single chip. In order to achieve continuous wavelength tuning, we increase the resistance of the laser to enhance the self-heating effect of the laser, which in turn expands the current-tuned wavelength range of the laser. The tunable 8 × 3 REC-DFB laser array employs a current tuning method. Consequently, in comparison with the conventional wavelength tuning methods relying on thermoelectric cooler (TEC), it can reach lower power consumption and faster continuous wavelength tuning. The proposed laser array is applicable to a 49 nm continuous wavelength tuning situation. Its output power is more than 38 mW, and all side mode suppression ratios (SMSRs) are higher than 40 dB. This research provides a new path for realizing semiconductor lasers with low power consumption and a wide tuning range.