Surfactant control of growth and interface quality in granular magnetic {CoCu}/Cu(111) superlattices

A magnetic superlattice has been prepared on Cu(1 1 1) using a surfactant ( Pb) to enhance layer-by-layer growth and codepositing Co and Cu within the magnetic layers, which consist thus of small, nearly superparamagnetic Co a ggregates within a Cu matrix. This procedure helps to maintain the fcc phas e of Co, producing well-defined interfaces with a negligible accumulation o f roughness during growth. Our magnetic measurements on this sample reveal a spin-glass-like behaviour, and demonstrate the validity of this method to produce samples with controlled properties. (C) 2001 Elsevier Science B.V. All rights reserved.