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arXiv · 2508.15914

Integrated magneto-optic based magnetometer: classical and quantum limits

Paolo Pintus·Heming Wang·Sudharsanan Srinivasan·Sergio Pinna·Duanni Huang·Yuya Shoji·Caroline A. Ross·John E. Bowers·Galan Moody
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Abstract

Magnetic field sensors with high sensitivity and spatial resolution have profoundly impacted diverse applications ranging from geo-positioning and navigation to medical imaging, materials science, and space exploration. However, the use of high-precision magnetometers is often limited due to their bulky size or low energy efficiency. In this work, we present the design, modeling and an experimental demonstration of an all-optical magnetometer based on silicon integrated photonics heterogeneously integrated with a magneto-optic thin film. By bonding a thin cerium-yttrium iron garnet layer onto an integrated silicon photonic interferometer, small magnetic field fluctuations can be detected through the non-reciprocal phase shift in the sensor. This strategy enables more than 80 dB of dynamic range with better than 40~pT/$\sqrt{\text{Hz}}$ sensitivity at room temperature. Importantly, by leveraging silicon photonics, the core platform is scalable through foundry manufacturing, and the ultra-low power requirements enable complete system integration with on-chip lasers, detectors, and quantum elements for enhanced sensitivity. This work provides a path to realizing a compact, scalable, room temperature magnetometer based on integrated photonic systems, opening new opportunities for ultra-sensitive and ultra-efficient magnetic field detectors.

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Paolo Pintus, Heming Wang, Sudharsanan Srinivasan, Sergio Pinna, Duanni Huang, Yuya Shoji, Caroline A. Ross, John E. Bowers, Galan Moody. 2025-08-21. Integrated magneto-optic based magnetometer: classical and quantum limits. https://arxiv.org/abs/2508.15914

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