STRUCTURE AND MAGNETIC-PROPERTIES OF EXCHANGE-SPRING SM-CO CO SUPERLATTICES/

We present structural and magnetic properties of epitaxial Sm-Co/Co su perlattice films prepared via magnetron sputtering. X-ray diffraction and cross-sectional transmission electron microscopy show that the fil ms are structurally coherent, The oriented nature of the interleaved f erromagnetically ''hard'' and ''soft'' layers comprising the superlatt ice provides a realization of the ideal nanostructure of exchange-spri ng magnets as well as a model system to study layer thickness dependen ces of the magnetic properties. The superlattice films have an effecti ve fourfold, in-plane magnetic anisotropy. Room-temperature hysteresis loops are relatively square and the demagnetization of the Co is reve rsible, as expected of exchange-spring magnets with aligned hard magne t layers.