2024-03-28T10:14:39Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/202982016-02-16T06:07:44Zcom_10261_31com_10261_3col_10261_284
Equilibrium spin-glass transition of magnetic dipoles with random anisotropy axes on a site-diluted lattice
Fernández, Julio F.
Alonso, Juan J.
6 pages, 7 figures, 1 table.-- PACS number s : 75.10.Nr, 75.10.Hk, 75.40.Mg
We study partially occupied lattice systems of classical magnetic dipoles which point along randomly oriented axes. Only dipolar interactions are taken into account. The aim of the model is to mimic collective effects in disordered assemblies of magnetic nanoparticles. From tempered Monte Carlo simulations, we obtain the following equilibrium results. The zero-temperature entropy approximately vanishes. Below a temperature Tc, given by kBTc=(0.95±0.1)xεd, where εd is a nearest-neighbor dipole-dipole interaction energy and x is the site occupancy rate, we find a spin-glass phase. In it, (1) the mean value (|q|), where q is the spin overlap, decreases algebraically with system size N as N increases, and (2) δ|q|≃0.5(|q|)√T/x, independently of N, where δ|q| is the root-mean-square deviation of |q|.
2010-01-25T13:10:58Z
2010-01-25T13:10:58Z
2009-06
artículo
Physical Review Letters 79(21): 214424.1-214424.6 (2009)
0031-9007
http://hdl.handle.net/10261/20298
10.1103/PhysRevB.79.214424
eng
http://dx.doi.org/10.1103/PhysRevB.79.214424
openAccess
American Physical Society