Measurement of magnetic fields by monitoring the Larmor precession of atomic spins is commonly used nowadays because of the high sensitivity and absolute measurement. This paper proposes a novel atomic magnetometer based on the self-sustaining method for large and fluctuating magnetic fields. In combination with the indefinitely persist Larmor precession signal, the sensitivity of the magnetometer increases following a much faster τ-1 rule beyond the atomic coherence lifetime. The maximum magnetic field have been experimentally demonstrated up to 40000 nT, the sensitivity achieved is 20 pT/√Hz and the frequency response bandwidth is 5 kHz, respectively. This magnetic field sensor is advantageous for applications requiring high sensitivity over a wide dynamic range such as geology and space physics.
The magnetic field is one of the most important physical observables with about all electromagnetic information. Larmor precession atomic magnetometers based on optical pumping experienced considerable attention recently. However, the sensitivity of this kind of atomic magnetometers is limited by their spin coherence time and the systematic noise. Here, we propose a self-sustaining atomic magnetic gradiometer that shows a superior 1/τ behavior in the magnetic field uncertainty measurement over time. The gradiometer is implemented by mixing and filtering the different frequency signals from two adjacent spin self-sustaining magnetometers with a baseline equal to 1 cm. The common-mode noise is suppressed and a gradient sensitivity of 200 fT/(√Hz=cm) is realized, being close to the shot noise limit.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.