Strain Induced Anisotropy Change in Ultrathin Fe Films Grown on MnAs(110)/GaAs(001)

C. HELMAN; ANA MARIA LLOIS

IEEE TRANSACTIONS ON MAGNETICS

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

Lugar: New York; Año: 2013 vol. 49 p. 4675 - 4678

0018-9464

Mechanical stress due to a misfit between a thin film and its substrate induces strains which can strongly modify the unstrained thinfilmproperties. One good and interesting example to study strain effects is given by ultrathin films of Fe epitaxially grown onMnAs(110)/GaAs(001). The MnAs(110) films show, at room temperature, coexistence of two structural phases, which organize themselves forminga striped pattern. The Fe epilayer senses the strain effects due to lattice mismatch and to the border constraints given by the stripedsubstrate. In this work, we are concerned with the consequences that this strain has on the magnetic anisotropy of the Fe thin film and tryto explain recent experimental results. These experiments indicate an easy axis rotation of the film Fe atoms sitting on one of the stripedphases. In order to have an approach to the understanding of the observed phenomenon, we make use of ab initio calculations and ofthe magnetoelastic model.We find that both the magnetoelastic model and the ab initio calculated spin orbit coupling point towards thestrain effects as the most important contribution to the observed easy axis rotation.