MnAs/NiAs magnetic multilayers on GaAs grown by molecular beam epitaxy

We have created a new class of epitaxial magnetic multilayers, consisting of ferromagnetic MnAs and nonmagnetic NiAs, on (001)GaAs substrates by molecular beam epitaxy. It was found that the growth plane of MnAs and NiAs is the (1100) of hexagonal crystal structure, and that the easy axis of magnetization of MnAs is in-plane, along the [1120] axis, which is parallel to the [110] of GaAs. Multi-stepped magnetic hysteresis are controllably realized, making this material promising for the application to multi-level non-volatile recording on semiconductors.