Development and application of transverse susceptometry to study the anisotropy field distribution, switching field distribution and the demagnetising factor tensor of magnetic materials

Project supervisor: Dr Steven McCann (

The study of assemblies of magnetic nanoparticles (MNP) continues to be an expanding and fundamentally important field of interest. Potential and real applications cover a wide range that includes: magnetic recording; biomedical treatments utilising hyperthermia (heating of MNPs under an ac field), either directly to cells/tissue or for the targeted release of drugs; room-temperature magnetic refrigeration.

Transverse susceptometry involves the application of orthogonal AC and DC magnetic fields to a sample and measuring its response. This response has a dependency on the sample’s constituent particles’ anisotropy and switching field distributions and the demagnetising factor tensor: information that can be deconvoluted from the response.

This project will involve the development of a transverse susceptometer to operate in both a linear and non-linear mode (sample response is measured either inline or orthogonal to the AC field direction). Analytical tools and numerical models will also need to be built up to allow deconvolution of the anisotropy information (which may extend to the use of neural networks as used in previous work) and for describing the demagnetisation tensor.