Effects of demagnetization fields on the angular dependence of coercivity of longitudinal thin film media

The field angle dependence of the coercive field of La0.67Sr0.33MnO3 thin films grown epitaxially on NdGaO3 substrates with different crystallographic orientations was determined. All films show uniaxial anisotropy. The angle dependence of the coercivity is best described by a two-phase model, explaining the strong increase in the coercive field for increasing field angles, away from the easy axis direction, as well as the sharp decrease for angles close to the hard direction. This implies that magnetization reversal starts with the depinning of domain walls, analogous to the Kondorsky model. With increasing field the reversal in the domains is not abrupt, but is determined by the gradual displacement of the domain walls. These results are of significance for understanding and possibly engineering of the switching behavior of magnetic tunnel junctions.

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Magnetization reversal mechanism in La0.67Sr0.33MnO3 thin films on NdGaO3 substrates

Mathews

Houwman

Boschker

et al. 2010

Crystallographic texture and angular dependence of coercivity of ordered CoPt thin film

Park

2005

Effect of crystallographic texture on the angular dependence of coercivity of ordered CoPt thin film was studied by successfully controlling the texture of the ordered CoPt thin film. We have developed, based on the Stoner–Wohlfarth interacting particles model, a micromagnetic simulation technique which can simulate the effect of distribution of magnetocrystalline easy axis on the magnetization behavior of thin film. The good agreement between the experiments and simulation suggested that the magnetization reversal in ordered CoPt thin film occurs not by the domain wall motion but by the Stoner–Wohlfarth interacting particles model.

Growth dependent magnetization reversal in Co2MnAl full Heusler alloy thin films

Barwal

Husain

Behera

et al. 2018

Angular dependent magnetization reversal has been investigated in Co2MnAl (CMA) full Heusler alloy thin films grown on Si(100) at different growth temperatures (Ts) by DC-magnetron sputtering. An M-shaped curve is observed in the in-plane angular (0°–360°) dependent coercivity (ADC) by magneto-optical Kerr effect measurements. The dependence of the magnetization reversal on Ts is investigated in detail to bring out the structure-property correlation with regards to ADC in these polycrystalline CMA thin films. This magnetization reversal (M-shaped ADC behavior) is well described by the two-phase model, which is a combination of Kondorsky (domain wall motion) and Stoner Wohlfarth (coherent rotation) models. In this model, magnetization reversal starts with depinning of domain walls, with their gradual displacement explained by the Kondorsky model, and at a higher field (when the domain walls merge), the system follows coherent rotation before reaching its saturation following the Stoner Wohlfarth model. Further, the analysis of angular dependent squareness ratio (Mr/Ms) indicates that our films clearly exhibited twofold uniaxial anisotropy, which is related to self-steering effect arising due to the obliquely incident flux during the film-growth.