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arXiv · 1208.4532

Catalyst-Free Growth of Millimeter-Long Topological Insulator Bi2Se3 Nanoribbons and the Observation of pi Berry Phase

L. Fang·Y. Jia·D. J. Miller·M. L. Latimer·Z. L. Xiao·U. Welp·G. W. Crabtree·W. -K. Kwok
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Abstract

We report the growth of single-crystalline Bi2Se3 nanoribbons with lengths up to several millimeters via a catalyst-free physical vapor deposition method. Scanning transmission electron microscopy analysis reveals that the nanoribbons grow along the (1120) direction. We obtain a detailed characterization of the electronic structure of the Bi2Se3 nanoribbons from measurements of Shubnikov-de Haas (SdH) quantum oscillations. Angular dependent magneto-transport measurements reveal a dominant two-dimensional contribution originating from surface states and weak contribution from the bulk states. The catalyst-free synthesis yields high-purity nanocrystals enabling the observation of a large number of SdH oscillation periods and allowing for an accurate determination of the pi-Berry phase, one of the key features of Dirac fermions in topological insulators. The long-length nanoribbons can empower the potential for fabricating multiple nanoelectronic devices on a single nanoribbon.

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L. Fang, Y. Jia, D. J. Miller, M. L. Latimer, Z. L. Xiao, U. Welp, G. W. Crabtree, W. -K. Kwok. 2012-08-22. Catalyst-Free Growth of Millimeter-Long Topological Insulator Bi2Se3 Nanoribbons and the Observation of pi Berry Phase. https://doi.org/10.1021/nl302989v

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