ABSTRACT
This chapter describes the characteristics of bulk and surface excitations, together with their symmetry aspects and the generalization to multilayer systems. Multilayer systems such as superlattices are an ideal way of achieving a large amount of surface or interface area. As regards the geometry, a method of enhancing the surface signal is to send the neutron beam at grazing incidence to the surface, and to measure the intensity of the Fresnel reflected beam. The chapter deals with the topics of sample growth, surface reconstruction and surface characterization. It outlines of some of the theoretical methods applied to bulk and surface excitations in linear materials. The chapter provides a preliminary survey of the experimental methods for detecting surface excitations. Surface excitations that generate electromagnetic fields can be investigated with optical techniques utilizing evanescent wave coupling between the juxtaposed surfaces of two media of different refractive index. The chapter also presents an overview of the key concepts discussed in this book.
