Slot-mode-coupled Optomechanical Crystals
CALIFORNIA INST OF TECH PASADENA T J WATSON LABS OF APPLIED PHYSICS
Pagination or Media Count:
We present a design methodology and analysis of 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 greater than 10exp6 optical mode of a separate nanobeam optical cavity. Using separate nanobeams provides flexibility, enabling the independent design and optimization of the optics and mechanics of the system. In addition, the small gap approximately equal to 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 g2 pi greater than 300 kHz in a Si3N4 system at 980 nm and g2 pi approximately equal to 900 kHz in a Si system at 1550 nm. The fact that large coupling strengths to GHz mechanical oscillators can be achieved in Si3N4 is important, as this material has a 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.
- Electrooptical and Optoelectronic Devices
- Acoustooptic and Optoacoustic Devices
- Quantum Theory and Relativity