Kohn anomalies in graphene nanoribbons
Author(s)
Dresselhaus, Mildred; Wakabayashi, Katsunori; Enoki, Toshiaki; Mori, Takanori; Takai, Kazuyuki; Saito, Riichiro; Murakami, Shuichi; Yamamoto, Masayuki; Sasaki, Ken-ichi; ... Show more Show less
DownloadSasaki-2009-Kohn anomalies in graphene nanoribbons.pdf (590.3Kb)
PUBLISHER_POLICY
Publisher Policy
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Terms of use
Metadata
Show full item recordAbstract
The quantum corrections to the energies of the Γ point optical phonon modes (Kohn anomalies) in graphene nanoribbons (NRs) are investigated. We show theoretically that the longitudinal optical (LO) modes undergo a Kohn anomaly effect, while the transverse optical (TO) modes do not. In relation to Raman spectroscopy, we show that the longitudinal optical modes are not Raman active near the zigzag edge, while the transverse optical modes are not Raman active near the armchair edge. These results are useful for identifying the orientation of the edge of graphene nanoribbons by G band Raman spectroscopy, as is demonstrated experimentally. The differences in the Kohn anomalies for nanoribbons and for metallic single-wall nanotubes are pointed out, and our results are explained in terms of pseudospin effects.
Date issued
2009-10Department
Massachusetts Institute of Technology. Department of PhysicsJournal
Physical Review B
Publisher
American Physical Society
Citation
Sasaki, Ken-ichi et al. “Kohn anomalies in graphene nanoribbons.” Physical Review B 80.15 (2009): 155450. © 2009 The American Physical Society
Version: Final published version
ISSN
1550-235X
1098-0121