Dispersion blue-shift in an aperiodic Bragg reflection waveguide

TL;DR

This paper investigates how aperiodic cladding designs in Bragg reflection waveguides cause a dispersion blue-shift, comparing Fibonacci, Thue-Morse, and Kolakoski patterns to periodic structures.

Contribution

It provides a comparative analysis of dispersion characteristics in aperiodic versus periodic Bragg waveguides, highlighting the universal blue-shift effect across different aperiodic patterns.

Findings

Aperiodic cladding causes a shift of dispersion curves to shorter wavelengths.

The blue-shift occurs regardless of the mode polarization.

The effect is consistent across Fibonacci, Thue-Morse, and Kolakoski patterns.

Abstract

A particular feature of an aperiodic design of cladding of Bragg reflection waveguides to demonstrate a dispersion blue-shift is elucidated. It is made on the basis of a comparative study of dispersion characteristics of both periodic and aperiodic configurations of Bragg mirrors in the waveguide system, wherein for the aperiodic configuration three procedures for layers alternating, namely Fibonacci, Thue-Morse and Kolakoski substitutional rules are considered. It was found out that, in a Bragg reflection waveguide with any considered aperiodic cladding, dispersion curves of guided modes appear to be shifted to shorter wavelengths compared to the periodic configuration regardless of the modes polarization.