Magnetic field and gradient standards using permanent magnets: Design considerations, construction and validation by nuclear magnetic resonance

The construction and characterization of static magnetic density flux and gradient standards by using permanent magnets is presented. In the first case, the field homogeneity is high enough to be measured by a nuclear magnetic resonance magnetometer, confirming the traceability of the standard. In the second case, a gradient standard is shown. The experimental results obtained by Hall probes are in agreement with theoretical calculations. Designing considerations about materials choice and mounting are also addressed.