Spin-Wave Instabilities in Spin-Transfer-Driven Magnetization Dynamics

Equatorial non-equilibrium states in magnetization dynamics of ferromagnets: Generalization of Suhl’s spin-wave instabilities

We investigate the nonlinear dynamics underlying the evolution of a 2-D ferromagnetic film with uniaxial anisotropy and an oscillating magnetic field. Considering the associated Landau-Lifshitz spin evolution equation with Gilbert damping included, we study the dynamics in terms of the stereographic variable. We identify several new fixed points for suitable choice of external field. In particu...

Current driven magnetization dynamics in helical spin density waves.

A mechanism is proposed for manipulating the magnetic state of a helical spin density wave using a current. It is shown that a current through a bulk metal with a helical spin density wave induces a spin transfer torque, which gives rise to a rotation of the order parameter. The use of spin transfer torque to manipulate the magnetization in bulk systems does not suffer from the obstacles seen f...

Spin-charge coupled dynamics driven by a time-dependent magnetization

The spin-charge coupled dynamics in a thin, magnetized metallic system are investigated. The effective driving force acting on the charge carriers is generated by a dynamical magnetic texture, which can be induced, e.g., by a magnetic material in contact with a normal-metal system. We consider a general inversion-asymmetric substrate/normal-metal/magnet structure, which, by specifying the preci...

Magnetic susceptibility measurements as a probe of spin transfer driven magnetization dynamics

Spin-transfer-induced precessional magnetization reversal

A magnetoelectronic device is proposed in which a spin-current pulse produces a rapid reversal of the magnetization of a thin film nanomagnet. A spin-transfer torque induces the reversal and the switching speed is determined by the precession frequency of the magnetization in a thin film element’s demagnetization field. Micromagnetic simulations show that this switching occurs above a threshold...