期刊
PHYSICAL REVIEW B
卷 79, 期 19, 页码 -出版社
AMER PHYSICAL SOC
DOI: 10.1103/PhysRevB.79.195409
关键词
band structure; defect states; disperse systems; electronic density of states; gold; photoemission; scanning tunnelling microscopy; scanning tunnelling spectroscopy; surface states
资金
- Fund for Scientific Research - Flanders (Belgium)
- Belgian Interuniversity Attraction Poles (IAP)
- Flemish Concerted Action (GOA)
We have investigated the contributions of surface-state electrons and bulk state electrons to the spatially oscillating local density of states (LDOS) of the Au(111) surface by scanning tunneling microscopy and spectroscopy at low temperatures. Based on the Fourier-transform images of LDOS maps obtained at various energies, we were able to determine the dispersion of the surface-state electrons in a broad range of energies, up to 3 eV. The energy versus wave vector dispersion relation was found to clearly deviate from the parabolic free-electron-like behavior at higher energies above 1 eV. Moreover, relying on two-dimensional Fourier-transform analysis, we develop an original approach to determine the dispersion behavior of bulk state electrons that are scattered at (sub)surface defects in the top atomic layers of the Au(111) surface. This additional set of electrons is found to exhibit a dispersion for the occupied states that is consistent with the calculated band structure of bulk Au and previous photoemission experiments. On the other hand, an anomalous bulk state dispersion behavior occurs in the empty state regime, where the wavelength of the spatial oscillations of the LDOS is observed to remain constant for the investigated energy range. This behavior is inconsistent with previous band-structure calculations and requires further theoretical investigation that takes into account the influence of inelastic electron scattering.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据