Comportamiento de paredes de dominio en nanohilos ferromagnéticos usando simulaciones micromagnéticas : comportamiento de paredes de dominio magnético en nanohilos de Co/Ru/Co acoplados antiferromagnéticamente.

Abstract

The study of magnetic domain walls in ferromagnetic nanostructures has grown in recent years due to their potential use in racetrack memories, sensors, etc., where control over their structure and behaviour is sought. Several structures have been analysed to find those more energy-efficient for practical use. Among these, synthetic antiferromagnetic and ferrimagnetic trilayer systems are highlighted. Here, the dependence of the structure and energy of domain walls in the mentioned trilayer systems concerning their dimensions is studied. The width was varied across five values from 100 to 500 [nm], and the layer thickness ratio was set at 1:1, 1:1.5, and 1:2. These systems were formed by Cobalt/Ruthenium/Cobalt with uniaxial anisotropy along the longitudinal axis with an anisotropy constant of 2 [kJ/m3] and an interlayer coupling constant of -0.5x10^-3[J/m2]. Five types of domain walls were found in the trilayer systems: parallel and antiparallel transverse walls, antivortex and radial antivortex walls, and vortex walls, with antiparallel walls having the lowest energy for the analysed dimensions. The parallel transverse walls exhibited a width reduction of up to 87% compared to a transverse wall in the single-layer system for a system width of 500 [nm]. For this type of wall, dimensions and structures differed in each Co layer and did not show a marked dependence on system dimensions. In contrast, a strong dependence on dimensions was found for antiparallel transverse walls, but the behaviour was similar in both layers.