MAGNETIC-PROPERTIES OF ULTRA-THIN IRON FILMS IN AG FE/AG SANDWICHES/

Ag/Fe/Ag sandwiches with the iron sublayer thickness in the range 1-8 nm are studied employing ferromagnetic resonance (FMR) and a vibrating sample magnetometer (VSM). A relative enhancement (20%) of the satura tion magnetization is confirmed for an iron sublayer thickness of abou t 2-4 nm. Extreme behaviour of the coercivity field is also observed i n the same region. This behaviour is ascribed to the Ag atoms implante d into the Fe sublayer. The Fe sublayer thickness related to zero magn etization is about 0.86 nm at RT. The energy of the surface anisotropy was determined from FMR using the Rado formula relating the effective magnetization to the thickness of the ferromagnetic layer.