Measuring Residual Magnetic Field in the Magnetic Shield with Magnetic Resonance Signal Width

Abstract

In this article, we present a novel method to measure the residual magnetic field in the magnetic shield. Because of the nonlinear Zeeman effect, the magnetic resonance width will grow with the increasing magnetic field. By detecting the dependence of the magnetic resonance signal width on the applied magnetic field, the residual magnetic field in the magnetic shield can be deduced. The error of the deduced value and the true value can be less than 1.5 nT. Higher sampling rate can result in less error.