High-precision control of static magnetic field magnitude, orientation, and gradient using optically pumped vapour cell magnetometry

TL;DR

This paper presents a highly precise system for controlling static magnetic field magnitude, orientation, and gradient using optically pumped vapor cell magnetometry, with applications in magnetic field mapping and calibration.

Contribution

The authors develop an integrated hardware and software system capable of defining and calibrating magnetic fields in all directions with high precision within a shielded environment.

Findings

Achieved one-sigma tolerances of 0.94 nT in magnitude, 5.9 mrad in orientation, and 13.0 pT/mm in gradient.

Demonstrated full 4π solid angle magnetic field control.

Mapped magnetometer signal dependence on static field orientation.

Abstract

An integrated system of hardware and software allowing precise definition of arbitrarily oriented magnetic fields up to |B| = 1 {\mu}T within a five-layer mumetal shield is described. The system is calibrated with reference to magnetic resonance observed between Zeeman states of the 6S$_{1/2}$ F = 4 $^{133}$Cs ground state. Magnetic field definition over the full 4{\pi} solid angle is demonstrated, with one-sigma tolerances in magnitude, orientation and gradient of {\delta}|B| = 0.94 nT, {\delta}{\theta} = 5.9 mrad and {\delta}$\nabla$ B = 13.0 pT/mm, respectively. This field control is used to empirically map Mx magnetometer signal amplitude as a function of the static field (B0) orientation.