Analysis of buried parabolic index segmented channel waveguides with z-dependent profile

► Buried parabolic index segmented channel waveguides with high-index segments having a z-dependent refractive index variation is presented. ► Analysis is used to study segmented waveguides fabricated using femtosecond laser inscription method. ► The analysis could be used to analyze periodic segmented waveguides with other transverse dependences than infinitely extended parabolic profiles, in terms of modal spot sizes, stable regions of operation, and effective index variation with period and duty cycle of segmentation. ► The analysis offers flexibility to change the gradation parameters and refractive index function along z to realize new waveguide devices.