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Updated: May 22, 2026

Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
Cavity optomechanical magnetometer
S Forstner1, S Prams, J Knittel
1School of Mathematics and Physics, University of Queensland, St Lucia, Queensland 4072, Australia.
Abstract:
A cavity optomechanical magnetometer is demonstrated. The magnetic-field-induced expansion of a magnetostrictive material is resonantly transduced onto the physical structure of a highly compliant optical microresonator and read out optically with ultrahigh sensitivity. A peak magnetic field sensitivity of 400 nT Hz(-1/2) is achieved, with theoretical modeling predicting the possibility of sensitivities below 1 pT Hz(-1/2). This chip-based magnetometer combines high sensitivity and large dynamic range with small size and room temperature operation.
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