# 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.

## Key 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.

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Source: https://tomesphere.com/paper/1704.00980