摘要
Metal superlattices are predicted to exhibit novel properties such as zone‐folding effects of electronic bands and phonon dispersions. Heterostructures consisting of rare‐earth magnetic metals Gd, Tm, and nonmagnetic elements Y, Lu with nearly perfect lattice match provide the unique opportunity of studying on the atomic scale the RKKY interaction, and the resultant magnetic ordering spin phases. However, such study would be fruitful only if the layer modulation direction coincides with the crystallographic C axis and a compositionwise sharp interface is achieved. Furthermore, because of the strong reactiveness of rare‐earth metals with gas impurities, these stringent film growth requirements can be best met by molecular‐beam‐epitaxial technique in a UHV environment. We have grown the rare‐earth metal single and multilayer films in a versatile UHV deposition system equipped with effusion cells and e‐beam evaporators. The typical growth rate is 1 monolayer/s, and the typical background pressure during growth is 1.0×10−10 Torr. With the in situ RHEED characterization, the preferred film growth direction, namely C axis, is controlled by optimizing the substrate temperature, and growth planes of substrates including sapphire, mica, and single crystal yttrium. Magnetic properties including anisotropy and moments versus temperature are studied by vibrating sample magnetometry on these multilayers with modulation wavelength varying from 20 to 200 Å. Results of x‐ray structure analysis, Rutherford backscattering depth profile, and the resistivity measurements will also be reported.