Pressure dependence of the uranium magnetic moment in β-UH3

Determine the pressure dependence of the uranium magnetic moment in β-UH3, using quantitative NV-magnetometry measurements of the sample’s magnetic stray field or element-specific high-pressure XMCD measurements.

Background

The study measures the pressure dependence of the Curie temperature of ferromagnetic β-UH3 using nitrogen-vacancy center magnetometry, but it does not quantitatively determine the uranium magnetic moment under pressure. The authors explain that extracting the magnetization from the magnetic stray field requires sufficiently well-controlled sample geometry, ideally a nearly spherical sample, to reduce uncertainties from demagnetization effects.

An alternative is to obtain element-specific information about the uranium 5f magnetic moment through X-ray magnetic circular dichroism (XMCD). However, extending XMCD to high-pressure diamond-anvil-cell experiments remains technically challenging because of the microscopic sample volume, restricted X-ray access, low-temperature requirements, and potentially high magnetic fields.