Surface, interface, and thin-film magnetism

Abstract

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Monte Carlo study of magnetic order at ferromagnetic and antiferromagnetic surfaces: Implications for spin-polarized photoelectron diffraction

“…The nature of magnetic order near surfaces and interfaces is a topic of high current interest, with experimental observations or theoretical predictions of Curie temperatures which may depend either on the thickness of an epitaxial ferromagnetic layer or may vary from the surface layer inward for a semi-infinite sample of homogeneous composition [1]. The temperature dependence of surface magnetic order is thus a key component of surface magnetism, particularly for systems of nanometer scale for which the fraction of surface atoms can become appreciable.…”

Neutron scattering studies of nanomagnetism and artificially structured materials

“…With such opportunities and challenges, it is valuable to examine the field, define our terms and limit the scope of the present document, to describing issues associated with artificially engineered materials and nanomagnetism. This report written in the spirit of the Falicov et al [1] and Kortright et al [2] reports, identifies opportunities and highlights promising approaches in neutron scattering.…”

“…properties of thin films [1]. However, theories that attempt to explain these properties generally assume "perfect" or regular crystalline interfaces.…”

“…Since the writing of the Falicov et al [1] report, powerful tools for the analysis of diffuse (non-specular) neutron and X-ray scattering first based on the distorted wave Born approximation [95,96] and more recently involving the "supermatrix" formalism [97,98,99,100] have been developed. Quantitative analysis of neutron or X-ray diffuse scattering to isolate magnetic roughness of surfaces and buried interfaces from structural and chemical interdiffusion is now possible [101].…”

“…A solution involves combining neutron reflectometry with inelastic neutron scattering (this approach is suggested in Falicov et al [1]). Bernhoeft et al, [155] using inelastic neutron scattering in forward geometry (the geometry used in reflectometry), observed spin-wave excitations in Ni 3 Al.…”