The interaction between spherical magnetic nanoparticles is investigated from micromagnetic simulations and ananlysed in terms of the leading dipolar interaction energy between magnetic dipoles. We focus mainly on the case where the particles present a vortex structure. In a first step the local magnetic structure in the isolated particle is revisited. For particles bearing a uniaxial magnetocr...

The electronic structure of diluted magnetic semiconductors is studied, especially focusing on the hole character. The Haldane-Anderson model is extend to a magnetic impurity, and is analyzed in the Hartree-Fock approximation. Due to the strong hybridization of an impurity d-states with host p-states, it is shown that holes are created in the valence band, at the same time the localized magneti...

Static and alternating magnetic field effects are introduced from the viewpoint of radical-radical interaction. Since the effect of magnetic field is much smaller than that of the electric field, the magnetic field dependence is a very sensitive measurement of the interaction between radicals. The low-field peak on the magnetic field effects and the spin-correlated radical pair polarization of ...