Determination of the Surface Magnetization of Fe(110) by Spin‐Polarized Low‐Energy Electron Diffraction

Abstract

a), R. FEDER3) (a), G. WALLER (b), and U. GRADMANN (b) Exchange and spin-orbit scattering asymmetries of spin-polarized low-energy electrons from Fe( 1 10) are measured at room temperature for several beams at constant energies as functions of the polar angle of incidence ("rocking curves"). Corresponding calculations by means of a relativistic multiple scattering formalism gave results in good agreement with the experimental data. The sensitivity of parts of the calculated curves to changes in the layer magnetization implies an enhancement of the topmost layer magnetization by about 36 to 40% relative to the bulk and possibly a reduction in the second layer. Further, a dominance of spin-down over spin-up inelastic scattering is deduced associated with 3p + 3d excitation. Die durch Austauschwechselwirkung und Spinbahnkopplung bedingten Streuasymmetrien bei der Beugung langsamer Elektronen an Fe( 1 10) werden bei Zimmertemperatur fur verschiedene Strahlen bei konstanter Energie als Funktionen des polaren Einfallswinkels gemessen. Entsprechende Rechnungen mittels eines relativistischen Vielfachstreuformalismus liefern Ergebnisse in guter obereinstimmung mit den experimentellen Daten. Aus der Empfindlichkeit von Teilen der berechneten Kurven gegeniiber Lnderungen der schichtabhangigen Magnetisierung folgt eine Erhohung der Magnetisierung der obersten Schicht um ca. 36 bis 40% relativ zum Volumenwert und moglicherweise eine Verringerung in der zweiten Schicht. AuDerdem folgt, daD bei der 3p -+ 3d-Anregung Minoritatselektronen starker inelastisch gestreut werden als Majoritatselektronen. 40'

Ultrathin antiferromagnetic films on a ferromagnetic substrate: a first-principles study of Mn on Fe(001)

“…For the uncovered Fe surface (top in figure 3), the surface magnetic moment is enhanced by about 34% with respect to the bulk magnetic moment (2.99 µ B versus 2.24 µ B ). A similar increase was also found for Fe(110) [40] (see also [41] for an overview). Upon coverage with Mn, the maximum magnetic moment in the Fe is shifted from layer 0 to layer −1, with the increase reduced to about 12%.…”

Ab initiocalculation of spin-polarized low-energy electron diffraction pattern for the systems Fe(001) and Fe(001)-p(1×1)O

“…The Fe atoms of the topmost layer have a higher magnetic moment when compared to the bulk value. This finding is known for magnetic atoms on surfaces and is related to the band narrowing of the d-states [36,37]. The trend for the decrease of the spin magnetic moments going to deeper Fe layers is similar for LSDA and LSDA+DMFT calculations.…”

Periodic Oscillations of the Surface Magnetization during the Growth of Co Films on Cu(001)

“…Ky,78.20.Ls The influence of the dimensionality on magnetism has been widely studied during the past years. A general trend is that the magnetic moment in ferromagnets like Fe, Co, and Ni is enhanced with reduced coordination number [1]: It was found that the magnetic moment of the free surface is enlarged with respect to that of the bulk [2][3][4][5]. From the enhanced moment at rough surfaces on Fe(110) Albrecht et al derived the magnetic moment for atoms at step sites to be larger by roughly 0.5m B than for those in the flat surface at T 300 K [6,7].…”