Jenichen, B.; Herfort, J.; Hentschel, T.; Nikulin, A.; Kong, X.; Trampert, A.; Zizak, I.: Residual disorder and diffusion in thin Heusler alloy films. Physical Review B 86 (2012), p. 075319
10.1103/PhysRevB.86.075319
Open Access Version (externer Anbieter)
Abstract:
Co2FeSi/GaAs(110) and Co2FeSi/GaAs(111)B hybrid structures were grown by molecular-beam epitaxy and characterized by transmission electron microscopy (TEM) and x-ray diffraction. The films contained inhomogeneous distributions of ordered L2(1) and B2 phases. The average stoichiometry was controlled by lattice parameter measurements; however, diffusion processes led to inhomogeneities of the atomic concentrations and the degradation of the interface, influencing long-range order. An average long-range order of 30-60% was measured by grazing-incidence x-ray diffraction, i.e., the as-grown Co2FeSi films were highly but not fully ordered. Lateral inhomogeneities of the spatial distribution of long-range order in Co2FeSi were found using dark-field TEM images taken with superlattice reflections.