Wavelength accuracy in distributed phase-shifted DFB lasers

In the wavelength-division-multiplexed transmission framework, we investigate the ability of the distributed phase-shifted distributed-feedback (DFB) structure by enlarging the ridge to fulfil the wavelength accuracy required for array fabrication. Measurements on three different phase-shift geometries indicate that the poor localization of the optical mode along the cavity is detrimental to the wavelength accuracy. This study points out the best solution for DFB structure implementable in arrays, using already validated low-cost and high-throughput technologies in a production environment.