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Title: Thin-film topological insulators for continuously tunable terahertz absorption

Abstract

One of the defining characteristics of a three-dimensional topological insulator (TI) is the appearance of a Dirac cone on its surface when it creates an interface with vacuum. For thin film TIs, however, the Dirac cones on opposite surfaces interact forming a small gap. For the case of three quintuple layers of Bi2Se3, we show that this gap can be continuously tuned between 128 meV and 0 meV with the application of modest perpendicular electric fields of less than 30 meV Å−1. Through both the Hamiltonian model and first-principles density functional theory calculations, we show that the inherent nonlinearity in realistic Dirac cone interaction leads to a gap which can be continuously tuned through the application of an external electric field. This tunability, coupled with the high optical absorption of thin film TIs, make this a very promising platform for terahertz and infrared detection.

Authors:
 [1];  [1]
  1. Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, Troy, New York 12180, USA
Publication Date:
Research Org.:
Rensselaer Polytechnic Inst., Troy, NY (United States); Univ. of California, Oakland, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1540154
Alternate Identifier(s):
OSTI ID: 1422862
Grant/Contract Number:  
SC0002623; AC02-05CH11231; DESC0002623
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Applied Physics Letters
Additional Journal Information:
Journal Volume: 112; Journal Issue: 9; Journal ID: ISSN 0003-6951
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
Physics

Citation Formats

West, D., and Zhang, S. B. Thin-film topological insulators for continuously tunable terahertz absorption. United States: N. p., 2018. Web. doi:10.1063/1.5016803.
West, D., & Zhang, S. B. Thin-film topological insulators for continuously tunable terahertz absorption. United States. doi:10.1063/1.5016803.
West, D., and Zhang, S. B. Mon . "Thin-film topological insulators for continuously tunable terahertz absorption". United States. doi:10.1063/1.5016803. https://www.osti.gov/servlets/purl/1540154.
@article{osti_1540154,
title = {Thin-film topological insulators for continuously tunable terahertz absorption},
author = {West, D. and Zhang, S. B.},
abstractNote = {One of the defining characteristics of a three-dimensional topological insulator (TI) is the appearance of a Dirac cone on its surface when it creates an interface with vacuum. For thin film TIs, however, the Dirac cones on opposite surfaces interact forming a small gap. For the case of three quintuple layers of Bi2Se3, we show that this gap can be continuously tuned between 128 meV and 0 meV with the application of modest perpendicular electric fields of less than 30 meV Å−1. Through both the Hamiltonian model and first-principles density functional theory calculations, we show that the inherent nonlinearity in realistic Dirac cone interaction leads to a gap which can be continuously tuned through the application of an external electric field. This tunability, coupled with the high optical absorption of thin film TIs, make this a very promising platform for terahertz and infrared detection.},
doi = {10.1063/1.5016803},
journal = {Applied Physics Letters},
issn = {0003-6951},
number = 9,
volume = 112,
place = {United States},
year = {2018},
month = {2}
}

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Free Publicly Available Full Text
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Works referenced in this record:

Topological invariants of time-reversal-invariant band structures
journal, March 2007


Topological Insulators in Three Dimensions
journal, March 2007


Z2classification of quantum spin Hall systems: An approach using time-reversal invariance
journal, May 2009


Colloquium: Topological insulators
journal, November 2010


Projector augmented-wave method
journal, December 1994


From ultrasoft pseudopotentials to the projector augmented-wave method
journal, January 1999


Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set
journal, October 1996