Abstract
The first coherent, single-crystal, magnetic rare-earth superlattices of Gd-Y were grown by metal molecular-beam epitaxy. X-ray structural analysis showed that the superlattices have a composition modulation of two atomic-layer-sharp interfaces with the modulation amplitude approaching 100%. The magnetic properties are consistent with a model in which the central Gd layers in each array behave like ideal ferromagnetic thin films even for as few as five atomic layers. The two interfacial Gd layers at the sides appear not to order ferromagnetically and have a susceptibility g independent of the number of atomic layers. © 1985 The American Physical Society.