Penetration of a magnetic wall into thin ferromagnetic electrodes of a nano-contact spin valve

TL;DR

This paper theoretically investigates how magnetic walls penetrate into thin ferromagnetic electrodes in nano-contact spin valves, revealing conditions that optimize oscillation power and thermal stability.

Contribution

It provides new insights into the penetration behavior of Neel and Bloch walls and identifies optimal nano-contact geometries for enhanced device performance.

Findings

Neel wall penetration is suppressed by increased demagnetization energy.

Optimal nano-contact radius and height maximize current-induced oscillation power.

Thermal stability of Bloch walls improves with larger radius or smaller height.

Abstract

We theoretically analyzed a magnetic wall confined in a nano-contact spin valve paying special attention to the penetration of the magnetic wall into thin ferromagnetic electrodes. We showed that, compared with the Bloch wall, the penetration of the Neel wall is suppressed by increases of the demagnetization energy. We found the optimal conditions of the radius and height of the nano-contact to maximize the power of the current-induced oscillation of the magnetic wall. We also found that the thermal stability of the Bloch wall increases when the nano-contact's radius increases or height decreases.