Thermal activation in permanent magnets
  The coercive field of permanent magnets decays with temperature. At non-zero temperature the system can overcome a finite energy barrier through thermal fluctuations. Using finite element micromagnetic simulations, we quantify this effect, which reduces coercivity in addition to the decrease of the coercive field associated with the temperature dependence of the anisotropy field, and validate the method through comparison with existing experimental data. 
Simon Bance, Johann Fischbacher, Alexander Kovacs, Harald Oezelt,   Franz Reichel and Thomas Schrefl
cond-mat.mtrl-sci