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Magnetic interactions in silica coated spherical nanoporous assemblies of CoFe2O4 nanoparticles have been investigated by low temperature field dependent remanent magnetization (MDCD and MIRM) and magnetization relaxation measurements. The synthesis procedure leads to the formation of spherical aggregates of about 50–60 nm in diameter composed of hexagonal shaped nanocrystals with shared edges. The negative deviation from the non-interacting case in the Henkel plot indicates the predominance of dipole–dipole interactions favouring the demagnetized state, although the presence of exchange interactions in the porous system cannot be excluded. The activation volume, derived from time dependent magnetization measurements, turns out to be comparable with the particle physical volume, thus indicating, in agreement with static and dynamic irreversible magnetization measurements, that the magnetization reversal actually involves individual crystals.

The magnetic properties of ultra-small (3 nm) CoFe2O4 nanoparticles have been investigated by DC magnetization measurements as a function of temperature and magnetic field. The main features of the magnetic behaviour are blocking of non-interacting particle moments (zero-field-cooled magnetization TmaxH40 K), a rapid increase of saturation magnetization (up to values higher than for the bulk material) at low T and an increase in anisotropy below 30 K due to the appearance of exchange bias. The low temperature behaviour is determined by a random freezing of surface spins. Localized spin-canting and cation distribution between the two sublattices of the spinel structure account quantitatively for the observed increase in saturation magnetization.

Angular magnetic properties of high anisotropy L10 CoPt (111) films showing a tilted magnetic easy axis configuration without an oblique grains microstructure were studied investigating the field dependence of remanent magnetization while rotating the magnetic field inside three intersecting planes. The out-of-plane tilting of the L10 c-axis (the easy axis of the tetragonal cell) was induced using a Pt (111) underlayer deposited onto a single crystal MgO substrate in a conventional Pulsed Laser Deposition (PLD) frontal deposition. The observed behavior is consistent with the presence of four easy axes with mutually orthogonal in-plane projections, symmetrically tilted at 36° with respect to the film plane. Such system can be used, like a common single-axis tilted medium, to record information in perpendicular mode, lowering the writing field to approximately 75% of the value along the easy direction, still maintaining the high medium thermal stability typical of the L10 alloy. Moreover, the in-plane charge compensation arising from this easy axis arrangement when a perpendicular writing field is applied, may favor a media noise reduction and better performances with respect to a single-axis tilted system.

The International Conference on Magnetism (ICM 2003) was held at the Palazzo dei Congressi in Rome, Italy, from July 27 to August 1, 2003. ICM 2003 was the 16th of the ICM Conference series, which are held every three years, organised under the auspices of the International Union for Pure and Applied Physics (IUPAP). The aim of these Conferences is to provide a forum for the international magnetism community to discuss new concepts, properties and developments in all branches of fundamental and applied magnetism, as well as research on magnetic materials and their applications. The Italian magnetism community was honoured to host ICM 2003 and proud for this opportunity given by IUPAP. The first ICM of the new millennium was held in the Eternal City and this coincidence made the event very special, giving a unique occasion for a meeting point between the past and the future, the old and the new. The Conference provided the state of the art of the research in magnetism, which proved to be particularly rich and exciting: new fascinating topics are emerging, new frontiers of knowledge are opening up, together with new perspectives for technological applications. ICM 2003 was a really international event and significantly exceeded all previous ICMs in number of participants (2081, from 60 countries through the world) (see Table 1 and Table 2; Fig. 1), in number of submitted abstracts (3006), and papers (2048). Submitted abstracts and papers were distributed among 13 Subject Categories. The distribution of submitted papers per Subject Category is reported in Table 3. Categories with the highest share were: 1 - Strongly correlated electron systems (collecting papers presented in SCES sessions) (17%); 5 - Magnetic structure and interactions (15%); 8 - Magnetism of nanoscopic/mesoscopic systems (14%); 4 - Spin electronics and magnetotransport (13%); 5 - Soft and hard magnetic materials (12%).