We review the current state of academic research in glass science in the United States. Our analysis is based on an evaluation of the number of journal articles published across the major segments of glass research. While the great majority of commercial opportunity is in silicate glasses and glass ceramics, together these represent less than one-quarter of publication activity. Academic research activity in glass ceramics is essentially nonexistent in the United States, while the attention given to metallic and chalcogenide glasses is disproportionately larger than the current industrial value for such glasses. We identify areas of glass research that are presently less explored, yet highly promising in terms of both industrial application and training students for future careers in industry.

The surface resistance and magnetic penetration depth in proximity-coupled superconductor/normalmetal (Nb/Al) bilayers are examined to study the electrodynamics of layered structures with spatially inhomogeneous superconducting order parameter. The effective penetration depth A, ,e( T) obeys KA, ,s( T)-T", where n~1, at low temperatures, distinctly different from the exponential behavior of Nb.An accompanying drop in the surface resistance R, occurs in the same temperature range. A model of the bilayer electrodynamics explicitly including the effects of proximity coupling is developed, and the behavior of both A, ,z and R, is consistently described. We find that a treatment of coherence effects in the proximity-coupled normal-metal layer is necessary to properly describe the behavior of R, ( T).

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