Published online by Cambridge University Press: 15 February 2011
Ultrathin epitaxial films grown in UHV – Fe(110) on Au(111) and Ag(111), Co(0001) on Au(111) – , sputtered Fe films between Ag and sputtered Fe/Au multilayers were studied by SQUID magnetometry and Mössbauer spectroscopy (CEMS). It could be shown that the magnetic anisotropy relative to the film normal, the, ground state magnetic moment per Fe atom and thermal spin excitations are affected by the structure of the films. In particular, a more 3-dimensional growth mode in the early state of film formation which is observed except in a certain temperature range around 300 K reduces the apparent magnetic interface anisotropy and the ferromagnetic ground state moment, and it enhances the thermal spin fluctuations and the tendency for superparamagnetic relaxation in the thinnest films.