Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan.
Phys Rev Lett. 2010 Aug 13;105(7):076802. doi: 10.1103/PhysRevLett.105.076802. Epub 2010 Aug 10.
A hexagonal deformation of the Fermi surface of Bi2Se3 has been for the first time observed by angle-resolved photoemission spectroscopy. This is in contrast to the general belief that Bi2Se3 possesses an ideal Dirac cone. The hexagonal shape is found to disappear near the Dirac node, which would protect the surface state electrons from backscattering. It is also demonstrated that the Fermi energy of naturally electron-doped Bi2Se3 can be tuned by 1% Mg doping in order to realize the quantum topological transport.
首次通过角分辨光电子能谱观察到 Bi2Se3 的费米面呈现六边形变形。这与普遍认为 Bi2Se3 具有理想狄拉克锥的观点形成对比。在狄拉克节点附近发现六边形形状消失，这将保护表面态电子免受背散射。此外，还证明了通过 1%Mg 掺杂自然电子掺杂的 Bi2Se3 的费米能可以进行 1%的调谐，以实现量子拓扑输运。
