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arXiv · 1212.1354

Structural and electronic properties of highly doped topological insulator Bi2Se3 crystals

Helin Cao·Suyang Xu·Ireneusz Miotkowski·Jifa Tian·Deepak Pandey·M. Zahid Hasan·Yong P. Chen
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Abstract

We present a study of the structural and electronic properties of highly doped topological insulator Bi2Se3 single crystals synthesized by the Bridgman method. Lattice structural characterizations by X-ray diffraction, scanning tunneling microscopy, and Raman spectroscopy confirmed the high quality of the as-grown single crystals. The topological surface states in the electronic band structure were directly re- vealed by angle-resolved photoemission spectroscopy. Transport measurements showed that the conduction was dominated by the bulk carriers and confirmed a previously observed bulk quantum Hall effect in such highly doped Bi2Se3 samples. We briefly discuss several possible strategies of reducing bulk conductance.

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Helin Cao, Suyang Xu, Ireneusz Miotkowski, Jifa Tian, Deepak Pandey, M. Zahid Hasan, Yong P. Chen. 2012-12-06. Structural and electronic properties of highly doped topological insulator Bi2Se3 crystals. https://doi.org/10.1002/pssr.201206457

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