Langevin simulation of thermally activated magnetization reversal in nanoscale pillars

摘要: Numerical solutions of the Landau-Lifshitz-Gilbert micromagnetic model incorporating thermal fluctuations and dipole-dipole interactions (calculated by fast multipole method) are presented for systems composed nanoscale iron pillars dimension 9nm x 150nm. Hysteresis loops generated under sinusoidally varying fields obtained, while coercive field is estimated to be 1979{+-}14 Oe using linear sweeps at T=0 K. Thermal effects essential relaxation magnetization trapped in a metastable orientation, such as happens after rapid reversal an external magnetic less than value. The distribution switching times compared simple analytic theory that describes with nucleation ends nanomagnets. Results also arrays nanomagnets oriented perpendicular flat substrate. Even separation 300 nm, where from neighboring only {approx}1 Oe, have significant effect on magnets.