Fermi-level pinning, charge transfer, and relaxation of spin-momentum locking at metal contacts to topological insulators [electronic resource].
- Washington, D.C. : United States. National Nuclear Security Administration, 2014.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy
- Physical Description:
- Article numbers 085,115 : digital, PDF file
- Additional Creators:
- Sandia National Laboratories
United States. National Nuclear Security Administration
United States. Department of Energy. Office of Scientific and Technical Information
- Topological insulators are of interest for many applications in electronics and optoelectronics, but harnessing their unique properties requires detailed understanding and control of charge injection at electrical contacts. Here we present large-scale ab initio calculations of the electronic properties of Au, Ni, Pt, Pd, and graphene contacts to Bi2Se3. We show that regardless of the metal, the Fermi level is located in the conduction band, leading to n-type Ohmic contact to the first quintuplet. Furthermore, we find strong charge transfer and band-bending in the first few quintuplets, with no Schottky barrier for charge injection even when the topoplogical insulator is undoped. Our calculations indicate that Au and graphene leave the spin-momentum locking mostly unaltered, but on the other hand, Ni, Pd, and Pt strongly hybridize with Bi2Se3 and relax spin-momentum locking. In conclusion, our results indicate that judicious choice of the contact metal is essential to reveal the unique surface features of topological insulators.
- Published through SciTech Connect.
Physical Review. B, Condensed Matter and Materials Physics 90 8 ISSN 1098-0121; PRBMDO AM
Catalin D. Spataru; François Léonard.
- Funding Information:
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