Electronic structure of atomic chains on vicinal Si(111)-Au - art. no. 035406

Unusual electronic states are found for gold-induced chain and ladder struc tures on vicinal Si(lll) surfaces, such as Si(111)5x2-Au and Si(557)-Au. As two-dimensional reference the Si(111)root 3x root3-Au surface is investiga ted. The highly stepped Si(557)-Au surface is metallic, despite an even ele ctron count. That is explained by two half-filled, nearly degenerate bands. On the Si(111)5x2-Au surface we find a band that changes continuously from one dimensional at its maximum to two dimensional at its minimum. It exhib its a pseudogap within 0.3 eV of the Fermi level E-F, where the spectral we ight is strongly reduced. Si(111)root3 x root3-Au exhibits an electron pock et at Gamma that changes its filling continuously with increasing Au covera ge.