Determination of magnetic anisotropy constants in Fe ultrathin film on vicinal Si(111) by anisotropic magnetoresistance

Abstract

The epitaxial growth of ultrathin Fe film on Si(111) surface provides an excellent opportunity to investigate the contribution of magnetic anisotropy to magnetic behavior. Here, we present the anisotropic magnetoresistance (AMR) effect of Fe single crystal film on vicinal Si(111) substrate with atomically flat ultrathin p(2 × 2) iron silicide as buffer layer. Owing to the tiny misorientation from Fe(111) plane, the symmetry of magnetocrystalline anisotropy energy changes from the six-fold to a superposition of six-fold, four-fold and a weakly uniaxial contribution. Furthermore, the magnitudes of various magnetic anisotropy constants were derived from torque curves on the basis of AMR results. Our work suggests that AMR measurements can be employed to figure out precisely the contributions of various magnetic anisotropy constants.

Planar Hall ring sensor for ultra-low magnetic moment sensing

“…Here, an hysteretic profile appears around the exchange bias field because the magnetic domain does not rotate coherently with the magnetic field when the magnetic field is compatible with the unidirectional field, H ex . 22 This is caused by a change in the minimum energy of the domain, which is described by the Stoner-Wohlfarth energy model 23 for domain rotation. This hysteresis relates to the domain wall motion at low magnetizing angle and would be reduced when increasing the applied field angle, a, from the easy axis of the sensor.…”

Direct observation of enhanced magnetism in individual size- and shape-selected 3d transition metal nanoparticles

“…The present calculations allow us to address this issue and to evaluate the actual contribution of K s to the magnetic energy barriers of spherical nanoparticles. Since K s is not a priori known and can significantly differ between various experimental reports, we have chosen to consider the range 0 < |K s /K 1 | < 800 in order to cover a large range of experimentally determined surface anisotropies deduced from thin film studies [74][75][76][77][78][79]. Further, K s is assumed to be constant; however, the model intrinsically takes the local environment of each atom into account and therefore yields a magnetic surface energy barrier, which depends locally on the actual coordination number [68,69].…”

Exchange bias effect modulated anisotropic magnetoresistance in Fe/YMnO3 multiferroic bilayers

“…4 shows the temperature dependence of AMR obtained with an applied magnetic field of 200 Oe. The external field is larger than the saturation field of the pure Fe layer in order to guarantee a true single-domain rotation and eliminate the ordinary magnetoresistance effect [8]. The resistances were collected with the sample rotating clockwise from 0-3601 and anticlockwise, arrows indicate the sense of rotation.…”

“…Therefore, an electric field modulated AMR may be realized by integrating the ferromagnet with the multiferroic materials in heterostructures. This effect shows great potential in the applications of the ultrahigh density magnetic recording media and spintronic materials [8]. In this work, the bilayers consisting of Fe and multiferroic YMnO 3 (YMO) were fabricated, and the exchange bias effect and AMR behaviors mediated by interfacial coupling were achieved.…”