Switching management in couplers with biharmonic longitudinal modulation of refractive index

TL;DR

This paper investigates how biharmonic longitudinal modulation of refractive index in optical couplers affects light propagation, revealing complex resonance behaviors and methods to control coupling through multi-frequency modulation.

Contribution

It introduces a detailed analysis of biharmonic modulation effects on coupler resonance structures, expanding understanding beyond single-frequency modulation.

Findings

Double-frequency modulation can suppress primary resonance.

Triple-frequency modulation causes fusion of primary and secondary resonances.

Resonance structures are significantly altered by multi-frequency modulation.

Abstract

We address light propagation in couplers with longitudinal biharmonic modulation of refractive index in neighboring channels. While simplest single-frequency out-of-phase modulation allows suppression of coupling for strictly defined set of resonant frequencies, the addition of modulation on multiple frequency dramatically modifies the structure of resonances. Thus, additional modulation on double frequency may suppress primary resonance, while modulation on triple frequency causes fusion of primary and secondary resonances.