ANGLE-RESOLVED PHOTOEMISSION FROM AN UNUSUAL QUASI-ONE-DIMENSIONAL METALLIC SYSTEM - A SINGLE-DOMAIN AU-INDUCED 5X2 RECONSTRUCTION OF SI(111)

Angle-resolved photoemission spectroscopy (ARPES), using HeI radiation , has been used to probe the occupied electronic states from a single domain of the Au-induced 5 x 2 reconstruction of Si(lll), a quasi-one- dimensional (quasi-1D) metallic system. The ARPES spectra recorded par allel (perpendicular) to the Au chain structure show a signature of a metallic (non-metallic) system. These experimental results are intrigu ing since, for the first time, spectral intensity at the Fermi level i s observed in a photoemission study of a quasi-1D metallic system.