Blocking temperature of interacting magnetic nanoparticles with uniaxial and cubic anisotropies from Monte Carlo simulations

Abstract

The low temperature behavior of densely packed interacting spherical single domain nanoparticles (MNP) is investigated by Monte Carlo simulations in the framework of an effective one spin model. The particles are distributed through a hard sphere like distribution with periodic boundary conditions and interact through the dipole dipole interaction (DDI) with an anisotropy energy including both cubic and uniaxial symmetry components. The cubic component is shown to play a sizable role on the value of the blocking temperature $T_b$ only when the MNP easy axes are parallel to the cubic easy direction ([111] direction for a negative cubic anisotropy constant). The nature of the collective low temperature state, either ferromagnetic or spin glass like, is found to depend on the ratio of the anisotropy to the dipolar energies characterizing partly the disorder in the system.

To be published in Journal of Magnetism and Magnetic Materials

References in corpus (4)

• Interplay between surface anisotropy and dipolar interactions in an assembly of nanomagnets
• Growth of a dynamical correlation length in an aging superspin glass
• Size and polydispersity effect on the magnetization of densely packed magnetic nanoparticles
• Magnetization of densely packed interacting magnetic nanoparticles with cubic and uniaxial anisotropies: A Monte Carlo study

Cited by in corpus (5)

• Thermal and magnetic phase transition properties of a binary alloy spherical nanoparticle: A Monte Carlo simulation study
• Phase diagram for ensembles of random close packed Ising-like dipoles as a function of texturation
• Nature of the spin-glass phase in dense packings of Ising dipoles with random anisotropy axes
• Tailoring Heat Dissipation in Ordered Arrays of Dipolar Coupled Magnetic Nanoparticles
• Including nanoparticle shape into macrospin models