Light tunneling inhibition in longitudinally modulated Bragg-guiding arrays

TL;DR

This paper demonstrates that out-of-phase longitudinal modulation of defect channels in Bragg-guiding arrays can nearly perfectly inhibit light tunneling between defects, especially for strongly localized modes near the gap center.

Contribution

It introduces a novel method of tunneling inhibition in waveguide arrays using out-of-phase longitudinal modulation of defect channels.

Findings

Tunneling can be almost completely suppressed with proper modulation.

Inhibition is most effective for modes near the gap center.

The method enables controlled light localization in waveguide arrays.

Abstract

We consider waveguide array in which defect channels with reduced refractive index are spaced periodically and the light guiding is achieved due to Bragg reflection. We show that tunneling between defects can be inhibited using out-of-phase longitudinal modulation of refractive index exclusively in defect channels. Tunneling inhibition is almost perfect for strongly localized modes with propagation constants close to the gap center.