We investigate single CoFeB nanotubes with hexagonal cross-section using dynamic cantilever magnetometry (DCM). We develop both an analytical model based on the Stoner-Wohlfarth approximation and a broadly applicable numerical framework for analyzing DCM measurements of magnetic nanostructures. Magnetometry data show the presence of a uniformly magnetized configuration at high external fields with μ0Ms=1.3±0.1 T and non-uniform configurations at low fields. In this low-field regime, comparison between numerical simulations and DCM measurements supports the existence of flux-closure configurations. Crucially, evidence of such configurations is only apparent because of the sensitivity of DCM to single nanotubes, whereas conventional measurements of ensembles are often obscured by sample-to-sample inhomogeneities in size, shape, and orientation
@article{arxiv.1512.00621,
title = {Dynamic cantilever magnetometry of individual CoFeB nanotubes},
author = {B. Gross and D. P. Weber and D. Rüffer and A. Buchter and F. Heimbach and A. Fontcuberta i Morral and D. Grundler and M. Poggio},
journal= {arXiv preprint arXiv:1512.00621},
year = {2016}
}