ABSTRACT
MnAs is a promising candidate for the integration of ferromagnetic materials with semiconductors as envisaged for example in spintronic devices [1,2]. Despite a very large and anisotropic misfit, high-quality MnAs can be grown epitaxially on GaAs(001) substrates using molecular beam epitaxy (MBE) [2-5]. The starting surface reconstruction and interface stoichiometry play a decisive role in determining epitaxial relationships and magnetic properties. Recently, the interface structure of the most interesting A-orientation (Fig. 1) has been explored by high-resolution electron microscopy [6] and the magnetic structure was imaged by magnetic force microscopy (MFM) [7]. However, the pronounced dependence of the magnetic properties on film thickness [3] is not yet well understood. In addition, the role of phase transitions during sample cooling after MBE growth has only recently been studied
Fig. 1. Scheme of the epitaxy of MnAs on GaAs(001).
