报告人：Prof. Philip Hofmann
Aarhus University, Denmark（丹麦奥胡斯大学）
surfaces of bismuth: from two-dimensional metals to the quantum spin Hall
摘要：In sharp contrast to the semi-metallic bulk, the surfaces of Bi form nearly two-dimensional metals, caused by the presence of metallic surface states. In a simple picture, the main reason for the existence of these states is the loss of inversion symmetry at the surface, combined with the strong spin-orbit interaction in Bi. The surface states are almost completely non-degenerate with respect to the electron's spin. This has interesting consequences for the electron dynamics, several examples of which will be given.
The Bi surfaces are electronically very similar to the surfaces of certain BiSb alloys which have been shown to be topological insulators and, indeed, Bi can be viewed as the parent material for these insulators. It will be shown that the surface of a vicinal Bi surface supports a one-dimensional non-degenerate state which bears great similarity to the edge state in the quantum spin Hall effect.
1992-1994 PhD student,Fritz-Haber-Institut der
Max-Planck-Gesellschaft, Berlin, Germany
1997-1998 work-group leader at the Fritz-Haber-Institut der Max-Planck-Gesellschaft
1998 - present professor, Institute for Storage Ring Facilities and
Ernst-Eckard-Koch award of the Berlin Electron Storage Ring Society BESSY (1994), Otto-Hahn-Medaille of the Max-Planck-Society (1995), Carl Ramsauer award of the AEG / Daimler Benz AG (1996), Visiting Professorship of the Leverhulme Trust (2007)
Contains circa 100 entries in international, peer-reviewed journals, including:
Nature Nanotechnology: 1
Physical Review Letters: 13
The work is highly cited with more than 1800 citations in total and an H-factor of 25.