Microscopic mechanisms of magnetization reversal

Abstract

Two principal scenarios of magnetization reversal are considered. In the first scenario all spins perform coherent motion and an excess of magnetic energy directly goes to a nonmagnetic thermal bath. A general dynamic equation is derived which includes a tensor damping term similar to the Bloch-Bloembergen form but the magnetization magnitude remains constant for any deviation from equilibrium. In the second reversal scenario, the absolute value of the averaged sample magnetization is decreased by a rapid excitation of nonlinear spin-wave resonances by uniform magnetization precession. We have developed an analytic k-space micromagnetic approach that describes this entire reversal process in an ultra-thin soft ferromagnetic film for up to 90^{o} deviation from equilibrium. Conditions for the occurrence of the two scenarios are discussed.

References in corpus (3)

• Non-uniform thermal magnetization noise in thin films: application to GMR heads
• Local Relaxation and Collective Stochastic Dynamics
• Nonlinear microscopic relaxation of uniform magnetization precession

Cited by in corpus (5)

• Macrospin Models of Spin Transfer Dynamics
• Magnetization reversal via internal spin waves in magnetic nanoparticles
• Strong magnon softening in tetragonal FeCo compounds
• Tuning the Curie temperature of FeCo compounds by tetragonal distortion
• Magnetization reversal and nonexponential relaxation via instabilities of internal spin waves in nanomagnets