Limits on Magnetically Induced Faraday Rotation from Polarized ${}^3$He Atoms

Abstract

Faraday rotation has become a powerful tool in a large variety of physics applications. Most prominently, Faraday rotation can be used in precision magnetometry. Here we report the first measurements of gyromagnetic Faraday rotation on a dense, hyperpolarized ${}^3$He gas target. Theoretical calculations predict the rotations of linearly polarized light due to the magnetization of spin-1/2 particles are on the scale of 10${}^{-7}$ radians. To maximize the signal, a ${}^3$He target designed to use with a multipass cavity is combined with a sensitive apparatus for polarimetry that can detect optical rotations on the order of 10${}^{-8}$ radians. Although the expected results are well above the sensitivity for the given experimental conditions, no nuclear-spin induced rotation was observed.