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arXiv · physics/0602109

Nonlinear magneto-optical rotation with frequency-modulated light in the geophysical field range

Abstract

Recent work investigating resonant nonlinear magneto-optical rotation (NMOR) related to long-lived ($\tau\ts{rel} \sim 1 {\rm s}$) ground-state atomic coherences has demonstrated potential magnetometric sensitivities exceeding $10^{-11} {\rm G/\sqrt{Hz}}$ for small ($\lesssim 1 {\rm \mu G}$) magnetic fields. In the present work, NMOR using frequency-modulated light (FM NMOR) is studied in the regime where the longitudinal magnetic field is in the geophysical range ($\sim 500 {\rm mG}$), of particular interest for many applications. In this regime a splitting of the FM NMOR resonance due to the nonlinear Zeeman effect is observed. At sufficiently high light intensities, there is also a splitting of the FM NMOR resonances due to ac Stark shifts induced by the optical field, as well as evidence of alignment-to-orientation conversion type processes. The consequences of these effects for FM-NMOR-based atomic magnetometry in the geophysical field range are considered.

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V. Acosta, M. P. Ledbetter, S. M. Rochester, D. Budker, D. F. Jackson-Kimball, D. C. Hovde, W. Gawlik, S. Pustelny, J. Zachorowski. 2006-02-15. Nonlinear magneto-optical rotation with frequency-modulated light in the geophysical field range. https://doi.org/10.1103/physreva.73.053404

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