Optical design of split-beam photonic crystal nanocavities

TL;DR

This paper presents the design of split-beam photonic crystal nanocavities with high quality factors, enabling mechanical excitations, by analyzing optical band structures and mode profiles.

Contribution

It introduces a novel split-beam cavity design with high Q-factors supported by detailed optical analysis, advancing photonic crystal cavity technology.

Findings

Quality factors exceeding 1 million predicted.

Supports mechanical excitations via physical gaps.

Designed for wavelengths around 1.6 micrometers.

Abstract

We design high quality factor photonic crystal nanobeam cavities formed by two mechanically isolated cantilevers. These "split-beam" cavities have a physical gap at the center, allowing mechanical excitations of one or both of the cavity halves. They are designed by analyzing the optical band structures and mode profiles of waveguides perforated by elliptical holes and rectangular gaps, and are predicted to support optical resonances with quality factors exceeding 1E6 at wavelengths of ~ 1.6 um.