Transition between Electron Localization and Antilocalization and Manifestation of the Berry Phase in Graphene on a SiC Surface
- Authors: Agrinskaya N.V.1, Lebedev A.A.1, Lebedev S.P.2, Shakhov M.A.1, Lahderanta E.3
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Affiliations:
- Ioffe Institute
- ITMO University
- Department of Mathematics and Physics, Lappeenranta University of Technology
- Issue: Vol 52, No 12 (2018)
- Pages: 1616-1620
- Section: Carbon Systems
- URL: https://journals.rcsi.science/1063-7826/article/view/204811
- DOI: https://doi.org/10.1134/S1063782618120023
- ID: 204811
Cite item
Abstract
It is shown that the transport properties of graphitized silicon carbide are controlled by a surface graphene layer heavily doped with electrons. In weak magnetic fields and at low temperatures, a negative magnetoresistance is observed due to weak localization. A crossover in the magnetoresistance from weak localization to weak antilocalization (the latter is the manifestation of the isospin in graphene) is observed for the first time in samples of this kind at elevated temperatures. A pronounced pattern of Shubnikov–de Haas oscillations is observed in strong magnetic fields (up to 30 T). This pattern demonstrated fourfold carrier spectrum degeneracy due to the double spin and double valley degeneracies. Also, the manifestation of the Berry phase is observed. The effective electron mass is estimated to be m* = 0.08m0, which is characteristic of graphene with a high carrier concentration.
About the authors
N. V. Agrinskaya
Ioffe Institute
Author for correspondence.
Email: nina.agrins@mail.ioffe.ru
Russian Federation, St. Petersburg, 194021
A. A. Lebedev
Ioffe Institute
Email: nina.agrins@mail.ioffe.ru
Russian Federation, St. Petersburg, 194021
S. P. Lebedev
ITMO University
Email: nina.agrins@mail.ioffe.ru
Russian Federation, St. Petersburg, 197101
M. A. Shakhov
Ioffe Institute
Email: nina.agrins@mail.ioffe.ru
Russian Federation, St. Petersburg, 194021
E. Lahderanta
Department of Mathematics and Physics, Lappeenranta University of Technology
Email: nina.agrins@mail.ioffe.ru
Finland, Lappeenranta