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arXiv · 1210.1874

The Interplay of Topological Surface and Bulk Electronic States in Bi2Se3

Megan Romanowich·Mal-Soon Lee·Duck-Young Chung·Jung-Hwan Song·S. D. Mahanti·Mercouri G. Kanatzidis·Stuart H. Tessmer
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Abstract

In this Letter we present scanning tunneling microscopy density-of-states measurements and electronic structure calculations of the topological insulator Bi2Se3. The measurements show significant background states in addition to the expected Dirac cone. Density functional calculations using a slab model and analysis of the partial density-of-states show that the background is consistent with bulk-like states with small amplitudes at the surface. The topological surface states coexist with bulk-like states in the valence band, appearing as a shoulder in the projected band structure. These results strongly support the picture suggested by recent scattering experiments of the quantum interference of topological and bulk-like surface states.

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Megan Romanowich, Mal-Soon Lee, Duck-Young Chung, Jung-Hwan Song, S. D. Mahanti, Mercouri G. Kanatzidis, Stuart H. Tessmer. 2012-10-05. The Interplay of Topological Surface and Bulk Electronic States in Bi2Se3. https://doi.org/10.1103/physrevb.87.085310

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