Slot-mode-coupled optomechanical crystals

Published

October 22, 2012

Author(s)

Marcelo I. Davanco, Jasper Chan, Amir H. Safavi-Naeini, Oskar Painter, Kartik A. Srinivasan

Abstract

We design a cavity optomechanical system in which a localized GHz frequency mechanical mode of a nanobeam resonator is evanescently coupled to a high quality factor (Q > 10^6) optical mode of a separate nanobeam optical cavity. Using separate nanobeams provides flexibility in independently designing the optics and mechanics of the system. In addition, the small gap ( approx. 25 nm) between the two resonators gives rise to a slot mode effect that enables a large zero-point optomechanical coupling strength to be achieved, with g=2pi > 300 kHz in a Si3N4 system at 980 nm and g/2pi approx. 900 kHz in a Si system at 1550 nm. The ability to achieve large coupling strengths to GHz frequency mechanics in Si3N4 is important due to its low intrinsic mechanical dissipation rate and broad optical transparency window, which allows operation throughout the visible and near-infrared. As an application of this platform, we consider wide-band optical frequency conversion between 1300 nm and 980 nm, using two optical nanobeam cavities coupled on either side to the breathing mode of a mechanical nanobeam resonator.

Citation

Optics Express

Volume

20

Issue

22

Pub Type

Journals

Download Paper

https://doi.org/10.1364/OE.20.024394

Keywords

Optomechanics, photonic crystals, phononic crystals

Citation

Davanco, M. , Chan, J. , Safavi-Naeini, A. , Painter, O. and Srinivasan, K. (2012), Slot-mode-coupled optomechanical crystals, Optics Express, [online], https://doi.org/10.1364/OE.20.024394 (Accessed October 13, 2025)