Prof. Andrew Geraci, Northwestern University

"Searching for Axions with Nuclear Magnetic Resonance"

Abstract: The quantum chromodynamics (QCD) axion could explain the lack of Charge-Parity (CP) violation in the strong interactions, while constituting all or part of the Dark matter in the universe, thus making it an “economical” solution to some of the greatest puzzles in cosmology and high energy physics. While much focus in the community has been on cosmic axion searches, axions can also generate novel spin-dependent short-range forces in tabletop experiments. The Axion Resonant InterAction Detection Experiment (ARIADNE) searches for the QCD axion using a technique based on nuclear magnetic resonance. The aim is to detect axion-mediated short-range interactions between laser-polarized 3He nuclei and an unpolarized tungsten source mass. The experiment has the potential to probe deep within the theoretically interesting regime for the QCD axion in the mass range of 0.01-10 meV. In this talk I will discuss the basic principle of the experiment, the current experimental status, and future prospects for detecting other varieties of novel spin-dependent axion-mediated fifth forces by using ferroelectric spin-polarized materials.