Conference Summary

Abstract

The overall conclusion at which one arrives from this meeting is that the field of X-ray and neutron scattering from surfaces is one of the most active, rapidly growing, and competitive fields in condensed matter and materials science research. This explosion of interest and activity can probably be traced to the increasing exploitation of synchrotron X-ray techniques for surface studies and also to the rapid development of neutron reflectometers at some of the best neutron facilities around the world. In this context it is worth recalling a little history. X-ray specular reflectivity studies were pioneered by Parratt in his classic work almost 40 years ago using a tube X-ray source, but using methods of data collection and analysis that are essentially those in use today. Present X-ray reflectivity studies, especially of liquids, owe much also to the pioneering work of Pershan and Als-Nielsen, and also Stuart Rice and his collaborators in the early eighties. One of the earliest demonstrations of grazing-incidence X-ray diffraction studies of surfaces was carried out by Eisenberger and Marra in 1979, while the concept of truncation rods and detailed structural studies of surfaces using X-rays were driven in the eighties by the work of Ian Robinson and his collaborators in the U.S., and Cowley and co-workers in Edinburgh. Neutron reflectivity also has a venerable history, going back, I believe, to Fermi just after World War II. Workers such as Passell and others at Brookhaven used the technique in the 1960’s to measure the scattering lengths of nuclei such as ³He. Specular reflectivity studies of polymer films were carried out by Stamm at Brookhaven in the early 1980’s. Much of the current impetus for magnetic and polymer surface studies has come from the successful programs started by Felcher at Argonne and the group led by Thomas and Penfold at the Rutherford CRISP facility. Zabel, Majrczak and others have more recently been among the first to extend the grazing incidence diffraction technique to neutrons. Finally, in the last few years, the role of non-specular or diffuse scattering from surfaces has begun to be explored with increasing interest.