A Caltech Library Service

Observation of a large-gap topological-insulator class with a single Dirac cone on the surface

Xia, Y. and Qian, D. and Hsieh, D. and Wray, L. and Pal, A. and Lin, H. and Bansil, A. and Grauer, D. and Hor, Y. S. and Cava, R. J. and Hasan, M. Z. (2009) Observation of a large-gap topological-insulator class with a single Dirac cone on the surface. Nature Physics, 5 (6). pp. 398-402. ISSN 1745-2473. doi:10.1038/nphys1274.

PDF (Supplementary Information) - Supplemental Material
See Usage Policy.


Use this Persistent URL to link to this item:


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.

Item Type:Article
Related URLs:
URLURL TypeDescription Information
Hsieh, D.0000-0002-0812-955X
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).
Funding AgencyGrant Number
Department of Energy (DOE)DE-FG02-05ER46200
Princeton Center for Complex MaterialsUNSPECIFIED
Department of Energy (DOE)DEFG02-07ER46352
National Science Foundation China (NSFC)10874116
Issue or Number:6
Record Number:CaltechAUTHORS:20140912-131757767
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:49668
Deposited By: Joy Painter
Deposited On:15 Sep 2014 17:38
Last Modified:10 Nov 2021 18:46

Repository Staff Only: item control page