Optical Magnetometry of Induced Extrinsic Magnetic Fields in Human-Sized Helmholtz Coils

We present simulation and analysis of the magnetic field evolution generated by human-sized copper coils when extrinsic metallic objects are introduced in their proximity. The magnetic field variation can be effectively detected by leveraging the Zeeman effect, when light interacts resonantly with alkali atoms confined in nanometric or micrometric thin cells. To precisely quantify these changes, we analyse spectra of light-atom interaction in the presence of a magnetic field and introduce an algorithm capable of measuring magnetic field variations induced by a relatively small iron sphere. The key strength of our approach lies in its robustness, as it can extract meaningful information from experimental spectra without requiring a direct reference spectrum.