Reversal time of the magnetization of magnetic nanoparticles at very low damping
arXiv:1312.4904 · doi:10.1103/PhysRevB.89.054408
Abstract
The magnetization reversal time of ferromagnetic nanoparticles is investigated in the very low damping regime. The energy-controlled diffusion equation rooted in a generalization of the Kramers escape rate theory for point Brownian particles in a potential to the magnetic relaxation of a macrospin, yields the reversal time in closed integral form. The latter is calculated for a nanomagnet with uniaxial anisotropy with a uniform field applied at an angle to the easy axis and for a nanomagnet with biaxial anisotropy with the field along the easy axis. The results completely agree with those yielded by independent numerical and asymptotic methods.
An extended version: 28 pages; 5 figures; Mathematica Programs