X-ray absorption magnetic circular dichroism (XMCD) This technique was pioneered by Schütz and co-workers . It is based on the changes in the absorption cross section of a magnetic material and uses circularly polarized photons . Through the well-known sum rules it allows to determine the relation between the orbital and the spin magnetic moments . A big advantage of this technique is that it is element specific and it is able to identify moment orientations in ultrathin films and monolayer magnetic materials. The X-ray microscopy also allows imaging with 100 nm. resolution.
(Micro-)Superconducting Quantum Interface Device
is a powerful technique to measure the net magnetization on a nanometer-size sample .
In 2001 Jamet et. al. have done the first magnetization reversal study on individual Co nanoparticle ( nm.) using a new setup. From those measurements they deduced the magnetic anisotropy magnitude  and that the behavior of individual nanoparticles follows the Néel-Arrhenius law .