Limits on magnetically induced Faraday rotation from polarized He3 atoms

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 measurements of gyromagnetic Faraday rotation on a dense, hyperpolarized $^{3}\mathrm{He}$ gas target. Theoretical calculations predict the rotations of linearly polarized light due to the magnetization of spin-1/2 particles on the scale of ${10}^{\ensuremath{-}7}$ radians. To maximize the signal, a $^{3}\mathrm{He}$ 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 ${10}^{\ensuremath{-}8}$ radians. Although the expected results are well above the sensitivity for the given experimental conditions, no nuclear-spin-induced rotation was observed.