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arXiv · 1303.1926

Non-trivial Surface-band Dispersion on Bi(111)

Yoshiyuki Ohtsubo·Luca Perfetti·Mark Oliver Goerbig·Patrick Le Fèvre·François Bertran·Amina Taleb-Ibrahimi
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Abstract

We performed angle-resolved photoelectron spectroscopy of the Bi(111) surface to demonstrate that this surface support edge states of non-trivial topology. Along the $\barΓ\bar{M}$-direction of the surface Brillouin zone, a surface-state band disperses from the projected bulk valence bands at $\barΓ$ to the conduction bands at $\bar{M}$ continuously, indicating the non-trivial topological order of three-dimensional Bi bands. We ascribe this finding to the absence of band inversion at the $L$ point of the bulk Bi Brillouin zone. According to our analysis, a modification of tight-binding parameters can account for the non-trivial band structure of Bi without any other significant change on other physical properties.

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Yoshiyuki Ohtsubo, Luca Perfetti, Mark Oliver Goerbig, Patrick Le Fèvre, François Bertran, Amina Taleb-Ibrahimi. 2013-03-08. Non-trivial Surface-band Dispersion on Bi(111). https://doi.org/10.1088/1367-2630%2F15%2F3%2F033041

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