Imaging Néel Relaxation of Superparamagnetic Nanoparticles using Diamond Magnetic Microscopy

Widefield diamond magnetic microscopy using nitrogen-vacancy centers is an emerging technique in various fields, including the study of magnetic materials. Superparamagnetic iron-oxide nanoparticles (SPIONs) are of interest for biomedical imaging applications, many of which would benefit from characterizing SPION Néel relaxation times at the single-particle level. Here, we report progress on the use of diamond magnetic microscopy to study the magnetic relaxation dynamics of single SPIONs and characterize their heterogeneity.