Uniform excitations in magnetic nanoparticles

Uniform excitations in magnetic nanoparticles

We present a short review of the magnetic excitations in nanoparticles below the superparamagnetic blocking temperature. In this temperature regime, the magnetic dynamics in nanoparticles is dominated by uniform excitations, and this leads to a linear temperature dependence of the magnetization and the magnetic hyperfine field, in contrast to the Bloch T(3/2) law in bulk materials. The temperat...

Uniform magnetic excitations in nanoparticles

Neutron study of magnetic excitations in 8-nm -Fe2O3 nanoparticles

Magnetic Excitations in Thulium

We have observed, for the first time, magnetic excitations in a single crystal of thulium, using inelastic neutron spectroscopy. In the ferrimagnetic phase three modes with energies around 4 meV, 8 meV and 15 meV were clearly seen. We have considered our results in terms of crystal field level schemes for thulium. The rare earth metal thulium (hcp, electronic configuration 4f12) exhibits a part...

Core-shell magnetic morphology of structurally uniform magnetite nanoparticles.

A new development in small-angle neutron scattering with polarization analysis allows us to directly extract the average spatial distributions of magnetic moments and their correlations with three-dimensional directional sensitivity in any magnetic field. Applied to a collection of spherical magnetite nanoparticles 9.0 nm in diameter, this enhanced method reveals uniformly canted, magnetically ...