Using Magnetic Tunnel Junctions (MTJs) Instead of Induction Coils in Nuclear Magnetic Resonance (NMR) to Detect Dark Matter

While dark matter remains elusive, a successful detection seems to require unconventional approaches with high sensitivity for small signals. One of the proposed methods to directly probe dark matter has been the utilization of pulsed nuclear magnetic resonance (NMR) to measure an oscillating torque on nuclear spins exerted by the axion-like darkmatter's oscillating magnetic field. However, all such NMR based experiments have relied on inductive coil detection, which innately has low sensitivity. Instead, we propose the application of magnetic tunnel junctions (MTJs), which uses the tunnel magnetoresistance (TMR) between two ferromagnets separated by a thin insulator to detect changes in the magnetic field. We explore how the sensitivity of MTJ based sensors compares to traditional inductive detection for axionlike dark matter detection.