通过表面碳掺杂调控Bi(2)Se(3)(0001)中的狄拉克点位置。

Tuning the Dirac point position in Bi(2)Se(3)(0001) via surface carbon doping.

作者信息

Roy Sumalay, Meyerheim H L, Ernst A, Mohseni K, Tusche C, Vergniory M G, Menshchikova T V, Otrokov M M, Ryabishchenkova A G, Aliev Z S, Babanly M B, Kokh K A, Tereshchenko O E, Chulkov E V, Schneider J, Kirschner J

机构信息

Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany.

Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany and Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Linnéstraße 2, 04103 Leipzig, Germany.

出版信息

Phys Rev Lett. 2014 Sep 12;113(11):116802. doi: 10.1103/PhysRevLett.113.116802. Epub 2014 Sep 9.

DOI:10.1103/PhysRevLett.113.116802

PMID:25259997

Abstract

Angular resolved photoemission spectroscopy in combination with ab initio calculations show that trace amounts of carbon doping of the Bi_{2}Se_{3} surface allows the controlled shift of the Dirac point within the bulk band gap. In contrast to expectation, no Rashba-split two-dimensional electron gas states appear. This unique electronic modification is related to surface structural modification characterized by an expansion of the top Se-Bi spacing of ≈11% as evidenced by surface x-ray diffraction. Our results provide new ways to tune the surface band structure of topological insulators.

摘要

角分辨光电子能谱结合第一性原理计算表明，Bi₂Se₃表面的痕量碳掺杂可使狄拉克点在体能带隙内实现可控移动。与预期相反，并未出现Rashba分裂的二维电子气态。这种独特的电子改性与表面结构改性有关，表面X射线衍射证明其特征为顶部Se - Bi间距扩大了约11%。我们的结果为调控拓扑绝缘体的表面能带结构提供了新方法。