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abstract: 'Nanoscale photonic crystal cavity optomechanical devices enable detection of nanomechanical phenomena with a sensitivity sufficient to observe quantum effects. Here we present the design of a one-dimensional air-mode photonic crystal cavity patterned in a silicon nitride nanobeam, and show that it forms the basis for cavity optomechanical split-beam and paddle nanocavity devices useful for force detection and nonlinear quantum sensing. The air-mode of this device is advantageous for optomechanical coupling, while also having ultrahigh optical quality factor $Q_o\sim 10^6$ despite its proximity to the light-line and the relatively low refractive index of silicon nitride. Paddle nanocavities realized from this device have a quadratic coupling coefficient $g^{(2)}/2\pi$ = 10 MHz/nm$^{2}$, and their performance within the context of quantum optomechanics experiments is analyzed.'
address: |
    Institute For Quantum Science And Technology, University of Calgary, AB, Canada, T2N 1N4\
    NRC National Institute For Nanotechnology, 11421 Saskatchewan Drive NW, Edmonton, AB, Canada, T6G 2M9
author:
- 'Chris Healey, Hamidreza Kaviani, and Paul E. Barclay'
bibliography:
- 'squidrefs.bib'
title: Air mode silicon nitride photonic crystals and their application to nonlinear quantum optomechanical sensing
---

Introduction
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One-dimensional photonic crystal cavities (PCC’s) patterned in nanobeams have many uses in both fundamental and practical applications 