Upraising wavelength exactitude in laser array with spatial hole burning suppression based on the reconstruction-equivalent-chirp technique

Appl Opt. 2022 Nov 10;61(32):9555-9561. doi: 10.1364/AO.453171.

Abstract

An equivalent corrugation pitch modulated distributed-feedback semiconductor multiwavelength laser array (MLA) with two equivalently assisted phase shifts (EAPSs) based on the reconstruction-equivalent-chirp technique is theoretically studied and experimentally demonstrated. The simulated results show that the longitudinal photon density distribution of the studied MLA is much more uniform than that of the MLA without EAPSs. Accordingly, the longitudinal spatial hole burning of the proposed MLA is therefore suppressed more effectively. The experimental results show that the studied MLA has good single-longitudinal-mode performance. The highest side mode suppression ratio (SMSR) is even up to 52.63 dB. Meanwhile, the tunable wavelength range of the investigated MLA is 25.94 nm under the thermal tuning scheme from 15.12°C to 46.93°C. All channels are within a wavelength deviation of ±0.001n m. The SMSRs are all above 38 dB.