Observation of a large-gap topological-insulator class with a single Dirac cone on the surface
Abstract
Recent experiments and theories have suggested that strong spin–orbit coupling effects in certain band insulators can give rise to a new phase of quantum matter, the so-called topological insulator, which can show macroscopic quantum-entanglement effects. Such systems feature two-dimensional surface states whose electrodynamic properties are described not by the conventional Maxwell equations but rather by an attached axion field, originally proposed to describe interacting quarks. It has been proposed that a topological insulator with a single Dirac cone interfaced with a superconductor can form the most elementary unit for performing fault-tolerant quantum computation. Here we present an angle-resolved photoemission spectroscopy study that reveals the first observation of such a topological state of matter featuring a single surface Dirac cone realized in the naturally occurring Bi_2Se_3 class of materials. Our results, supported by our theoretical calculations, demonstrate that undoped Bi_2Se_3 can serve as the parent matrix compound for the long-sought topological device where in-plane carrier transport would have a purely quantum topological origin. Our study further suggests that the undoped compound reached via n-to-p doping should show topological transport phenomena even at room temperature.
Additional Information
© 2009 Macmillan Publishers Limited. Received 26 December 2008; Accepted 2 April 2009; Published online 10 May 2009. We thank N. P. Ong, B.A. Bernevig, D. Haldane and D.A. Huse for discussions. The synchrotron X-ray experiments are supported by the DOE-BES (contract DE-FG02-05ER46200) and materials synthesis is supported by the NSF-MRSEC (NSF-DMR-0819860) at Princeton Center for Complex Materials at Princeton University. Theoretical work is supported by the US Department of Energy, Office of Science, Basic Energy Sciences contract DEFG02-07ER46352, and benefited from the allocation of supercomputer time at NERSC and Northeastern University's Advanced Scientific Computation Center (ASCC). D.Q. was partly supported by the NNSF-China (grant No. 10874116).Attached Files
Supplemental Material - nphys1274-s1.pdf
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Additional details
- Eprint ID
- 49668
- DOI
- 10.1038/nphys1274
- Resolver ID
- CaltechAUTHORS:20140912-131757767
- DE-FG02-05ER46200
- Department of Energy (DOE)
- DMR-0819860
- NSF
- Princeton Center for Complex Materials
- DEFG02-07ER46352
- Department of Energy (DOE)
- 10874116
- National Science Foundation China (NSFC)
- Created
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2014-09-15Created from EPrint's datestamp field
- Updated
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2021-11-10Created from EPrint's last_modified field