Temperature-dependent ferromagnetic-resonance study in ultrahigh vacuum: Magnetic anisotropies of thin iron films

Abstract
20- to 350-Å Fe thin films have been prepared on W(110) and studied by ferromagnetic resonance in ultrahigh vacuum. The magnetic anisotropy of Fe films and its temperature dependence were determined independently from the angular and the frequency dependences of the resonance field in the temperature range between 300 and 600 K. A switching of the easy axis of the magnetization from [1¯10] to [001] was confirmed at a film thickness of about 110 Å. This is disucssed in terms of surface and volume contributions to the anisotropy energy.