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arXiv · 1804.08194

Nanotesla-level, shield-less, field-compensation-free, wave-mixing-enhanced body-temperature atomic magnetometry for biomagnetism

Feng Zhou·Eric Y. Zhu·Yvonne L. Li·E. W. Hagley·L. Deng
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Abstract

We report an optical inelastic-wave-mixing-enhanced atomic magnetometry technique that results in nT-level magnetic field detection at temperatures compatible with the human body without magnetic shielding, zero-field compensation, or high-frequency modulated phase-locking spectroscopy. Using Gaussian magnetic pulses that mimic the transient magnetic field produced by an action potential on a frog's nerve, we demonstrate more than 300,000-fold (550-fold) enhancement of magneto-optical rotation signal power spectral-density (power amplitude) over the conventional single-beam $\Lambda-$scheme atomic magnetometry method. This new technique may bring possibilities for extremely sensitive magnetic field imaging of biological systems accessible via an optical fiber in clinical environments.

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Feng Zhou, Eric Y. Zhu, Yvonne L. Li, E. W. Hagley, L. Deng. 2018-04-22. Nanotesla-level, shield-less, field-compensation-free, wave-mixing-enhanced body-temperature atomic magnetometry for biomagnetism. https://arxiv.org/abs/1804.08194

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