arXiv:1807.03619 · Physical Review Letters

Self-Calibrating Vector Atomic Magnetometry through Microwave Polarization Reconstruction

Tobias Thiele, Yiheng Lin, Mark O. Brown, Cindy A. Regal

Published Oct 8, 2018• 36 citations

Abstract

Atomic magnetometry is one of the most sensitive ways to measure magnetic fields. We present a method for converting a naturally scalar atomic magnetometer into a vector magnetometer by exploiting the polarization dependence of hyperfine transitions in rubidium atoms. First, we fully determine the polarization ellipse of an applied microwave field using a self-calibrating method, i.e., a method in which the light-atom interaction provides everything required to know the field in an orthogonal laboratory frame. We then measure the direction of an applied static field using the polarization ellipse as a three-dimensional reference defined by Maxwell's equations. Although demonstrated with trapped atoms, this technique could be applied to atomic vapors, or a variety of atomlike systems.

DOI: 10.1103/physrevlett.121.153202

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