Magnetization patterning induced by electrical spin-polarized current in nanostripes

TL;DR

This paper investigates how electrical spin-polarized currents and the resulting Oersted field influence magnetization patterns in ferromagnetic nanostripes, revealing the persistence of certain structures and the formation of a single domain wall at high currents.

Contribution

It provides a combined numerical and analytical analysis of the effects of spin-torque and Oersted field on magnetization patterns in nanostripes, highlighting the formation of a stable domain wall at high currents.

Findings

Oersted field does not destroy periodical magnetization structures.

Strong currents lead to a stationary state with a single domain wall.

The shape of the domain wall remains constant as current increases.

Abstract

The combined action of a transverse spin-polarized current and the current-induced {\O}rsted field on long ferromagnetic nanostripes is studied numerically and analytically. The magnetization behavior is analyzed for stripes with various widths and for all range of the applied current density. It is established that {\O}rsted field does not destroy periodical magnetization structures induced by the spin-torque, e.g. vortex-antivortex crystal and cross-tie domain walls. However, the action of the {\O}rsted field disables the saturation state for the strong currents: a stationary state with a single longitudinal domain wall appears instead. Shape of this wall remains constant with the current increasing. The latter phenomenon is studied both numerically and analytically.