The electronic structure of Sr2RuO4 is investigated by high angular
resolution ARPES at several incident photon energies. We address the
controversial issues of the Fermi surface (FS) topology and of the van Hove
singularity at the M point, showing that a surface state and the replica of the
primary FS due to (sqrt2 x sqrt2) surface reconstruction are responsible for
previous conflicting interpretations. The FS thus determined by ARPES is
consistent with the de Haas-van Alphen results, and it provides additional
information on the detailed shape of the alpha, beta and gamma sheets.Comment: Final version for Physical Review Letters. Revtex, 4 pages, 4
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