Inverse photoemission studies of two quasi-one-dimensional overlayer systems

Photoemission studies of Au chains on Si(111) surfaces, Si(111)-Au(5 X 2), have identified a 'metallic' surface band parallel to the chains. The signature of the metallic nature is strong emission intensity at the Fermi level. In contrast, it has recently been established that bulk quasi-one-dimensional systems have vanishing emission intensity at the Fermi level. To further our understanding of these low dimensional systems, we have studied Si(111)-Au(5 x 2) and Si(111)-In(4 X 1), which is also quasi-one-dimensional, with inverse photoemission. (C) 1998 Elsevier Science B.V.