Pseudomorphic growth of Fe monolayers onIr(001)−(1×1): From a fct precursor to a bct film

Abstract

The epitaxial growth of Fe monolayers on the unreconstructed Ir 001 surface was investigated experimentally by determining film structure, morphology, stress, and magnetism. Our combined quantitative low energy electron diffraction LEED and cantilever stress results indicate pseudomorphic Fe growth with a constant in-plane film strain in an almost perfect layer-by-layer growth mode from 0–10 layers. The combination of the structural analysis by LEED with stress measurements suggests that the first two layers of Fe grow as a face-centered tetragonally fct distorted precursor. Further deposition of Fe leads to the growth of a bodycentered tetragonally distorted phase on top of the fct precursor, which retains its structure. The magnetooptical Kerr effect reveals that the Fe film is ferromagnetic with an in-plane easy magnetization direction along Fe 100 .