Epitaxial τMnAl/NiAl magnetic multilayers on AlAs/GaAs Available to Purchase

We have successfully grown a novel type of epitaxial metallic multilayers consisting of ultrathin ferromagnetic tetragonal τMnAl and nonmagnetic (CsCl‐type) NiAl on (001) GaAs substrates using molecular beam epitaxy. Reflection high energy electron diffraction and cross‐sectional transmission electron microscopy (TEM) show that monocrystalline MnAl/NiAl multilayers are formed with the expected epitaxial orientations and that the c axis of the tetragonal structure of the ultrathin MnAl film is aligned perpendicular to the substrate. Composition modulation is clearly evidenced by TEM even when the thickness of each MnAl and NiAl layer is as thin as 3 monolayers. Perpendicular magnetization of the MnAl/NiAl multilayers is shown by both magnetization and magnetotransport measurements at room temperature, exhibiting remarkably square hysteresis loops, high values (M_r≳300 emu/cm³) of remanent magnetization, and relatively low values of coercive field (0.2<H_c<1 kOe).