Surface structure and magnetic properties of MnAs epilayers grown on vicinal GaAs(001) substrates
Résumé
In this study, we have investigated the influence of the vicinality on the surface morphology of MnAs/GaAs(001) epilayers at the nanoscale. The microscopic structure of the MnAs surface is strongly affected by the miscut angle of the substrate, while the characteristic MnAs alpha-beta micronic self-organized stripes pattern remains largely unaffected. Even though the surface morphology is quite different from epilayers deposited on nominal substrates (no miscut), the magnetic properties of the films grown on vicinal substrates are nearly unaltered. That is, the temperature for the onset of the beta phase, for decreasing temperature, the coercive field, and the remnant magnetization are similar to films grown on nominal substrates. These findings open interesting prospects concerning the use of MnAs/GaAs(001) epilayers as temperature-dependent striped templates for the subsequent growth of magnetic thin films and the formation of a great variety of nanostructures.