MAN-MADE MATERIALS - AN EXCITING AREA FOR HYPERFINE-INTERACTION INVESTIGATIONS

Man-made low-dimensional magnetic systems including surfaces, interfac es and multilayers, have attracted a great amount of attention in the past decade because, as expected, the lowered symmetry and coordinatio n number offer a variety of opportunities for inducing new and exotic phenomena and so hold out the promise of new device applications. Loca l spin density functional (LSDF) ab initio electronic-structure calcul ations employing the full-potential-linearized augmented-plane-wave (F LAPW) method have played a key role in the development of this excitin g field by not only providing a clearer understanding of the experimen tal observations but also predicting new systems with desired properti es. One of the striking successes of theory in the last decade has bee n the calculation of hyperfine fields at surfaces and interfaces. Conc urrently, several groups have followed the pioneering work of Korecki and Gradmann and have measured hyperfine fields at surfaces and interf aces. In this paper, we review new features of hyperfine-interaction i nvestigations in man-made materials which emphasizes how the close int erplay of theoretical determinations and experiment are essential beca use the hyperfine field is not proportional to the magnetization and s o interpretations of experiment are totally dependent on theory.