27 research outputs found
DB2 COST-EFFECTIVENESS ANALYSIS OF PREGABALIN FOR THE MANAGEMENT OF NEUROPATHIC PAIN ASSOCIATED WITH DIABETIC PERIPHERAL NEUROPATHY IN MEXICO
PCV52 ECONOMIC EVALUATION OF DALTEPARIN FOR THE MANAGEMENT OF THROMBOEMBOLIC VENOUS DISEASE (VTE) AFTER TOTAL KNEE ARTHROPLASTY IN MEXICO
Magnetic Anisotropy of a Single Cobalt Nanoparticle
Using a new microSQUID set-up, we investigate magnetic anisotropy in a single
1000-atoms cobalt cluster. This system opens new fields in the characterization
and the understanding of the origin of magnetic anisotropy in such
nanoparticles. For this purpose, we report three-dimensional switching field
measurements performed on a 3 nm cobalt cluster embedded in a niobium matrix.
We are able to separate the different magnetic anisotropy contributions and
evidence the dominating role of the cluster surface.Comment: 4 pages, 8 figure
Structure and Magnetism of well-defined cobalt nanoparticles embedded in a niobium matrix
Our recent studies on Co-clusters embedded in various matrices reveal that
the co-deposition technique (simultaneous deposition of two beams : one for the
pre-formed clusters and one for the matrix atoms) is a powerful tool to prepare
magnetic nanostructures with any couple of materials even though they are
miscible. We study, both sharply related, structure and magnetism of the Co/Nb
system. Because such a heterogeneous system needs to be described at different
scales, we used microscopic and macroscopic techniques but also local selective
absorption ones. We conclude that our clusters are 3 nm diameter f.c.c
truncated octahedrons with a pure cobalt core and a solid solution between Co
and Nb located at the interface which could be responsible for the magnetically
inactive monolayers we found. The use of a very diluted Co/Nb film, further
lithographed, would allow us to achieve a pattern of microsquid devices in view
to study the magnetic dynamics of a single-Co cluster.Comment: 7 TeX pages, 9 Postscript figures, detailed heading adde
Onset of non-collinear magnetism in small Fe clusters
The onset of noncollinear magnetism in small FeN
clusters is investigated by using a rotational invariant tight-binding
Hamiltonian. The ground-state local magnetic moments, magnetic order and average magnetic moments
are calculated as a function of the Coulomb exchange integral J. Representative results
for Fe3 and Fe5 show that the noncollinear magnetic solutions are the most stable.
A variety of qualitatively different self-consistent
solutions is obtained as a function of J. This includes magnetic solutions with collinear and noncollinear spin arrangements. Our calculations are compared with
previous density-functional results. Extensions and limitations of our work are also pointed out