Wavelength trimming technology for multiple-wavelengthdistributed-feedback laser arraysby photo-induced refractive index change

The authors propose a novel post-fabrication wavelength-error correction method in distributed-feedback (DFB) laser arrays without using external active control circuitry, namely ‘wavelength trimming technology’. Se-based chalcogenide glass has been used which has a refractive index change of ~1% induced by light irradiation as a part of a waveguide of 1.55 µm DFB laser and wavelength trimming of 0.14 nm is demonstrated.