PERIODIC CHANGE OF THE MAGNETIC AND STRUCTURAL-PROPERTIES WITH THICKNESS OF ER THIN-FILMS

Er thin films with thicknesses ranging from 88 to 196 Angstrom and wit h their c-axis perpendicular to the film plane were prepared on the Nb buffer layer deposited on Al2O3(11 (2) over bar 0) substrate. The mag netic phase transition temperatures showed periodic change as a functi on of Er thickness with a period of 20 Angstrom, which corresponds to about seven atomic layers of Er. The periodic change in the magnetic p roperty was found to be accompanied by that in the c-axis lattice cons tant. A possible origin of the periodic changes is discussed.