Bondarenko L V, Matetskiy A V, Yakovlev A A, Tupchaya A Y, Gruznev D V, Ryzhkova M V, Tsukanov D A, Borisenko E A, Chukurov E N, Denisov N V, Vilkov O, Vyalikh D V, Zotov A V, Saranin A A
Institute of Automation and Control Processes FEB RAS, 690041 Vladivostok, Russia. School of Natural Sciences, Far Eastern Federal University, 690950 Vladivostok, Russia.
J Phys Condens Matter. 2014 Feb 5;26(5):055009. doi: 10.1088/0953-8984/26/5/055009. Epub 2014 Jan 17.
Adsorption of ∼0.1 ML of Na onto the Si(111)√3 × √3-Au surface held at 300 °C has been found to induce pronounced changes in its structural and electronic properties. Domain wall networks, characteristic of the pristine surface, are removed completely, leading to the formation of a highly ordered homogeneous surface. The original atomic arrangement of the Si(111)√3 × √3-Au is preserved and Na atoms occupy T4 adsorption sites at the centers of surface Si trimers. Upon Na adsorption, a pronounced metallic S1 surface-state band develops. It is characterized by a large spin splitting (momentum splitting at the Fermi level Δk∥ = 0.027 Å(-1) and consequent energy splitting ΔEF = 110 meV), large electron filling (on the order of 0.5 electrons per √3 × √3 unit cell) and small effective electron mass of (0.028 ± 0.006)me. The natural consequence of the latter properties is a high surface conductivity of the Si(111)√3 × √3-(Au, Na) surface.
已发现，在300°C下，约0.1 ML的Na吸附到Si(111)√3 × √3 - Au表面会使其结构和电子性质发生显著变化。原始表面特有的畴壁网络被完全去除，从而形成高度有序的均匀表面。Si(111)√3 × √3 - Au的原始原子排列得以保留，且Na原子占据表面Si三聚体中心的T4吸附位点。Na吸附后，会形成一个明显的金属性S1表面态能带。其特征为大的自旋分裂（费米能级处的动量分裂Δk∥ = 0.027 Å⁻¹，进而导致能量分裂ΔEF = 110 meV）、大的电子填充（每√3 × √3晶胞约0.5个电子）以及小的有效电子质量(0.028 ± 0.006)me。后述性质的自然结果是Si(111)√3 × √3 - (Au, Na)表面具有高表面电导率。
