Epitaxial ferromagnetic tgr;hyphen;MnAl films on GaAs

摘要

We report the growth of epitaxial tgr;hyphen;MnAl ferromagnetic films on GaAs substrates by molecular beam epitaxy (MBE). Reflection highhyphen;energy electron diffraction and xhyphen;ray diffraction show that the tgr;hyphen;phase films grow with thecaxis of the tetragonal unit cell normal to the lcub;100rcub;GaAs substrate surface. In the bulk, tgr;hyphen;MnAl is a metastable ferromagnetic phase with uniaxial magnetocrystalline anisotropy. The large hysteresis observed in the Hall resistance versus applied magnetic field suggests that the easy magnetization direction is indeed parallel to thecaxis in the MBEhyphen;grown films. The growth of these ferromagnetic films with perpendicular magnetization on compound semiconductor substrates creates the possibility of novel devices that combine magnetic memory and magnetohyphen;optic functions with semiconductor electronics and photonics.