Quantum Interference in Macroscopic Crystals of Nonmetallic Bi2Se3
Photoemission experiments have shown that Bi2Se3 is a topological insulator. By controlled doping, we have obtained crystals of Bi2Se3 with nonmetallic conduction. At low temperatures, we uncover a novel type of magnetofingerprint signal which involves the spin degrees of freedom. Given the mm-sized crystals, the observed amplitude is 200-500x larger than expected from universal conductance fluctuations. The results point to very long phase-breaking lengths in an unusual conductance channel in these nonmetallic samples. We discuss the nature of the in-gap conducting states and their relation to the topological surface states.
J. G. Checkelsky et al., "Quantum Interference in Macroscopic Crystals of Nonmetallic Bi2Se3," Physical Review Letters, vol. 103, no. 24, American Physical Society (APS), Dec 2009.
The definitive version is available at http://dx.doi.org/10.1103/PhysRevLett.103.246601
Keywords and Phrases
Breaking Length; Conductance Channels; Conducting State; Low Temperatures; Quantum Interference; Spin Degrees Of Freedom; Surface State; Universal Conductance Fluctuations; Crystals
International Standard Serial Number (ISSN)
Article - Journal
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