John Unguris (National Institute of Standards and Technology, Gaithersburg, Md.): "Our paper examines the relationship between atomic order and magnetic coupling in artificially grown magnetic multilayer structures. Some of these structures have the fascinating property that the magnetization in alternate magnetic layers may either be aligned parallel or antiparallel, depending on the thickness of the nonmagnetic spacer layer between them. Measuring the thickness dependence of the magnetic coupling in these layers, which may be only a few atomic layers thick, is essential for understanding the origins of the coupling in these technologically important materials.
"We approached the problem in a different manner from that of previous researchers. Instead of trying to grow and measure many samples reproducibly with different spacer thicknesses, we grew a single sample, which consisted of an Fe/Cr/Fe `sandwich' with a wedge-shaped Cr spacer layer. We then used a scanning electron microscope to measure the direction of ...
