Surface states and their possible role in the superconductivity of MgB2

We report layer-Korringa-Kohn-Rostocker calculations for bulk and surface states as well as the corresponding angle resolved photoemission (ARPES) intensities of MgB2. Our theoretical results reproduce very well the recent ARPES data by Uchiyama et al., cond-mat/0111152. At least two surface states are assigned. Consequences of SFS on the anisotropy of the upper critical fields and other properties in the superconducting state of small grains in micropowder samples are briefly discussed.Comment: 4pages, 6figures, corrected typos, references adde