The structure of an (Formula presented) surface has been studied by using scanning tunneling microscopy (STM), synchrotron radiation photoemission spectroscopy (SRPES), and x-ray photoelectron diffraction (XPD). Honeycomblike images are observed by STM measured at a bias voltage of -1.4 V. Similar images are also observed at +1.5 V, although the intensity of the alternative corner of a hexagon is depressed, resulting in a threefold symmetry. (Formula presented) and (Formula presented) XPD patterns show that sulfur atoms rarely exchange the fourfold arsenic sites. Three surface components are found in the (Formula presented) spectra. On the other hand, no surface components are found in the (Formula presented) spectra. Based on the STM, SRPES, and XPD results, a probable structure model for the (Formula presented) surface is proposed. The experimental XPD patterns are in good agreement with the calculated ones.
|Number of pages||6|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2000 Jan 1|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics