Cute Chains On Cu(111) By Deposition Of One-Third Of A Monolayer Of Te: Atomic And Electronic Structure

The surface atomic and electronic structure after deposition of one-third of a monolayer Te on Cu(111) was determined using a combination of low-energy electron diffraction (LEED), scanning tunneling microscopy and spectroscopy (STM/STS), angle-resolved single and two-photon photoelectron spectroscopy (ARPES/AR-2PPE), and density functional theory (DFT) calculations. Contrary to the current state in literature, Te does not create a two-dimensional surface alloy but forms Cu2Te2 adsorbate chains in a (2 root 3 x root 3)R30 degrees superstructure. We establish this by a high-precision LEED-IV structural analysis with Pendry R factor of R = 0.099 and corroborating DFT and STM results. The electronic structure of the surface phase is dominated by an anisotropic downward dispersing state at the Fermi energy E-F and a more isotropic upward dispersing unoccupied state at E - E-F = +1.43 eV. Both states coexist with bulk states of the projected band structure, and are therefore surface resonances.