Hysteresis and anisotropy in ultrathin Fe/Si(001) films

Abstract

It is challenging to investigate the magnetic anisotropy of Fe/Si(001) film in the case a limited magnetic field strength, when both coherent rotation and domain wall displacement coexist in the magnetization reversal process. Owing to the domain wall displacement, the magnetization reversal switching field is far lower than the magnetic anisotropy field, and, consequently, only the magnetization reversal process near easy axis can be treated as coherent rotation. Here, we record the slope of the magnetic torque curve of an iron film grown on a Si(001) substrate measured near the easy axis by anisotropic magnetoresistance (AMR) to separate the coherent rotation of magnetization reversal process from domain wall displacement. Furthermore, the magnitudes of various magnetic anisotropy constants were derived from the magnetic torque curves. Our work suggests that the AMR at low fields can clearly separate the detailed contributions of various magnetic anisotropies when domain wall displacement existed in Fe(001) ultrathin film. We also report on the hysteresis behavior of such films as measured by magneto-optic Kerr effect. V C 2014 AIP Publishing LLC. [http://dx.

2D Metals by Repeated Size Reduction

“…[45][46][47] Here, we have provided experimental evidence of Fe nanosheets exhibiting in both vertical and horizontal magnetic fi elds. Here, N is inversely related to the factor l / d (where l is length in the magnetic fi eld and d is the width).…”

The effect of annealing temperature on the magnetic anisotropy in Co ultrathin film on MgO(001) substrate

“…Figure 4(a) and 4(b) show the typical torque curves τ ϕ M of Sample II and Sample III respectively calculated from the angular dependence of AMR curves. 13,20 The red lines show the fitting results based on the Eq. (3).…”

“…The detailed information has been described in our previous works. 12,13 The angular dependence of AMR was measured by standard four-probe lock-in technology which was performed by a 5mA alternating sensing current at 193 Hz. easy direction along the [-110].…”

Magnetization reversal process in Fe/Si (001) single-crystalline film investigated by planar Hall effect

“…[22,23] In the previous work, the UMA in Fe/Si (001) is very small compared with the MCA and the domain wall pinning energy. [10,11] Due to the existence of K u2 , the local minima position will shift a small angle δ , so we set the local minima of Eq. ( 2) to be at θ = −δ , 90 • + δ , 180 • − δ , and 270 • + δ , where δ = 1 2 sin −1 (K u2 /K 1 ).…”

“…[10] Furthermore, we find that the magnetization reversal process of Fe/Si (001) film has been proved to be the combination of coherent rotation and domain wall displacement when the external field is smaller than the anisotropy field by torque measurement with anisotropic magnetoresistance. [11] In the present work, the 40-ML single crystal iron film is reported to be grown on a vicinal Si (001) substrate using a flat ultrathin c(2 × 2) iron silicide seed layer and the PHE is used to investigate the magnetization reversal process and determine the domain wall pinning energy. The magnetization reversal process is found to be dominated by different mechanisms at different external field angles.…”