REORIENTATION PHASE-TRANSITION BEHAVIOR IN METASTABLE EPITAXIAL COBALT-COPPER ALLOYS

We report experimental results on the ferromagnetic critical behavior of cobalt and metastable cobalt-copper alloy two-dimensional layers CuxCo1-x epitaxially grown on Cu(001). Copper alloying reduces the magnitude of the cobalt magnetic moment and introduces a magnetization component normal to the film. Reorientation of the magnetization back into the plane occurs via a second-order phase transition at a temperature which is lower than the film Curie temperature. We discuss these results in light of the recent predictions of Pescia and Pokrovsky.