The crystallographic and electronic band structure of In induced reconstruction of Si(335)-Au surface have been studied with reflection high electron energy diffraction and angle resolved photoemission spectroscopy in ultrahigh vacuum conditions. The photoemission spectra recorded along chains show strongly dispersive band crossing the Fermi level while dispersionless spectra are found in the perpendicular direction. Diffraction experiments support one-dimensional character of the structures. A simple model of In reconstructed Si(335)-Au surface has been put forward.
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The electronic band structure of the Si(557) and Si(335) surfaces covered with monoatomic Au chains produced in UHV conditions, is investigated in detail by angle-resolved photoelectron spectroscopy (ARPES), especially for the surface state bands near the Fermi energy. The ARPES spectra in the plane parallel to step edges for Si(557)-Au vicinal surface show strongly dispersive electron energy bands, characteristic of one-dimensional structure. The band dispersion is also calculated within tight-binding model, with two adjustable coupling parameters t{ and t2, for the first and second neighbors along the chains, respectively, and compared with that determined from the photoemission experiment. The scanning tunneling microscopy (STM) imaging and reflection high energy electron diffraction (RHEED) studies enabled us to determine atomic chain separation and its internal structure. The study shows that the structural anisotropy of these surfaces induces highly anisotropic electronic structure.
Vicinal Si(111) surfaces were investigated by Reflection High Energy Electron Diffraction (RHEED). The samples were cut 14.42° off the (111) plane in (112) direction. The Si(533) plane with a regularly distributed terraces and monoatonic steps was obtained by depositing of 0.28 monolayer (ML) of Au on a clea vicinal surface and annealing it up to 900 K. The length of the terraces and the height of the steps were determined equal to 12.27 Å and 3.22 Å , respectively. The structure of metallic Pb layers deposited on the vicinal suraces was studied. Up to the thickness equal to 4ML we observed the growth of Pb in from of one-and two-dimensional structures. Above this thickness only two-dimensional crystallites exist. The mean sizes of the Pb crystallities were determined from the intensity distribution of the diffraction spots.
The Pb film have been grown on Si(111)-(6x6)Au substrate. Electron transmission through the film was measured as a function of incident electron energy. Two types of structures were observed in collected current. One of them strongly depends on the thicknees of Pb layers, characteristic of the quantum size effect. The other is associated with the bulk band structure of Pb. The value of inner potential of Pb equal to 14 eV was determined.
We have studied in situ the reflectance difference (RD) during depositon of ultrathin Pb epitaxial film onto Si(111)-(6x6)Au substrates held at 100 K in UHV conditions. S- and p-polarized radiation with energy within the range from 0.5 eV to 3.0 eV was used to excite electron transitions in the Pb samples showing the quantum size effects (QSE). The optical reflection data were analysed using classical and QSE theories. Observed thicknees-dependet reflectivity variations were correlated with previously measurmed electrical resistivity oscillations. Scattering time of electrons involved in the electrical resistivity measurements. Evidences of optical diamagnetic and paramagnetic response of electrons in the metallic quantum well are prasented and discussed.
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