Realistic finite temperature simulations of magnetic systems using quantum statistics

Abstract

We have performed realistic atomistic simulations at finite temperatures using Monte Carlo and atomistic spin dynamics simulations incorporating quantum (Bose-Einstein) statistics. The description is much improved at low temperatures compared to classical (Boltzmann) statistics normally used in these kind of simulations, while at higher temperatures the classical statistics are recovered. This corrected low-temperature description is reflected in both magnetization and the magnetic specific heat, the latter allowing for improved modeling of the magnetic contribution to free energies. A central property in the method is the magnon density of states at finite temperatures and we have compared several different implementations for obtaining it. The method has no restrictions regarding chemical and magnetic order of the considered materials. This is demonstrated by applying the method to elemental ferromagnetic systems, including Fe and Ni, as well as Fe-Co random alloys and the ferrimagnetic system GdFe${}_3$ .

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Cited by in corpus (13)

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• Prediction of the Curie temperature considering the dependence of the phonon free energy on magnetic states
• Size and temperature dependent magnetization of iron nanoclusters
• Atomistic Simulation of Phonon and Magnon Thermal Transport across the Ferro-Paramagnetic Transition
• Magnetochemical effects on phase stability and vacancy formation in fcc Fe-Ni alloys
• Tetragonal CuMnAs alloy: role of defects
• Numerical Simulations of a Spin Dynamics Model Based on a Path Integral Approach
• Effects of magnetic excitations and transitions on vacancy formation: cases of fcc Fe and Ni compared to bcc Fe
• Magnetochemical coupling effects on thermodynamics, point-defect formation and diffusion in Fe-Ni alloys: a theoretical study
• Magnonic Proximity Effect in Insulating Ferro- and Antiferromagnetic Trilayers
• Absence of topological Hall effect in Fe${}_x$Rh${}_{100-x}$ epitaxial films: revisiting their phase diagram