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

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 نشر من قبل Eric Zhu
 تاريخ النشر 2018
  مجال البحث فيزياء
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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 frogs 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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