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arXiv · 1201.5618

Observation of Fermi-energy dependent unitary impurity resonances in a strong topological insulator Bi2Se3 with scanning tunneling spectroscopy

M. L. Teague·H. Chu·F. -X. Xiu·L. He·K. -L. Wang·N. -C. Yeh
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Abstract

Scanning tunneling spectroscopic studies of Bi2Se3 epitaxial films on Si (111) substrates reveal highly localized unitary impurity resonances associated with non-magnetic quantum impurities. The strength of the resonances depends on the energy difference between the Fermi level ({E_F}) and the Dirac point ({E_D}) and diverges as {E_F} approaches {E_D}. The Dirac-cone surface state of the host recovers within ~ 2Å spatial distance from impurities, suggesting robust topological protection of the surface state of topological insulators against high-density impurities that preserve time reversal symmetry.

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M. L. Teague, H. Chu, F. -X. Xiu, L. He, K. -L. Wang, N. -C. Yeh. 2012-01-26. Observation of Fermi-energy dependent unitary impurity resonances in a strong topological insulator Bi2Se3 with scanning tunneling spectroscopy. https://doi.org/10.1016/j.ssc.2012.01.041

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