Krasovskii E E, Höcker J, Falta J, Flege J I
Departamento de Física de Materiales, Universidad del Pais Vasco UPV/EHU, 20080 San Sebastián/Donostia, Spain. Donostia International Physics Center (DIPC), 20018 San Sebastián/Donostia, Spain. IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain.
J Phys Condens Matter. 2015 Jan 28;27(3):035501. doi: 10.1088/0953-8984/27/3/035501. Epub 2014 Dec 24.
Electron scattering by oxygen monolayers on the Ru(0 0 0 1) surface is studied both experimentally and theoretically. Sharp transmission resonances at low energies are revealed and established to originate from critical points of a special kind in the complex band structure of the substrate. Electron reflection from the clean and oxidized Ru(0 0 0 1) is measured for kinetic energies up to 40 eV at normal incidence for oxygen coverages of 1/4, 1/2, 3/4, and one monolayer. The reflection spectra R(E) are analyzed using a Bloch-waves based ab initio scattering theory. In addition to the substrate-induced resonances the reconstructed (2 × 1) and (2 × 2) surfaces show surface resonances due to pre-emergent secondary diffraction beams. The R(E) spectra are shown to give unambiguous evidence of the hcp stacking of the oxygen layer.
对氧单层在Ru(0 0 0 1)表面的电子散射进行了实验和理论研究。揭示了低能下的尖锐透射共振，并确定其源于衬底复能带结构中一种特殊类型的临界点。在垂直入射时，测量了氧覆盖率为1/4、1/2、3/4和单层时，动能高达40 eV的清洁和氧化Ru(0 0 0 1)的电子反射。使用基于布洛赫波的从头算散射理论分析反射光谱R(E)。除了衬底诱导的共振外，重构的(2×1)和(2×2)表面由于预出现的二次衍射束而显示出表面共振。R(E)光谱被证明能明确证明氧层的hcp堆积。
