On-chip scalable optomechanical magnetometers
Abstract
The dual-resonant enhancement of mechanical and optical response in cavity optomechanical magnetometers enables precision sensing of magnetic fields. In previous working prototypes of such magnetometers, a cavity optomechanical system is functionalized by manually epoxy-bonding a grain of magnetostrictive material. While this approach allows proof-of-principle demonstrations, practical applications require more scalable and reproducible fabrication pathways. In this work, we scalably fabricate optomechanical magnetometers on a silicon chip, with reproducible performance across different devices, by sputter coating a magnetostrictive film onto high quality toroidal microresonators. Furthermore, we demonstrate that thermally annealing the sputtered film can improve the magnetometer sensitivity by a factor of 6.3. A peak sensitivity of 585 pT/Hz^1/2 is achieved, which is comparable with previously reported results using epoxy-bonding.
Cite
@article{arxiv.1805.09660,
title = {On-chip scalable optomechanical magnetometers},
author = {Bei-Bei Li and Douglas Bulla and Varun Prakash and Stefan Forstner and Ali Dehghan-Manshadi and Halina Rubinsztein-Dunlop and Scott Foster and Warwick P. Bowen},
journal= {arXiv preprint arXiv:1805.09660},
year = {2020}
}
Comments
6 pages, 5 figures