Robustness of the Edge States in Graphene Quantum Hall System: Does the Chiral Symmetry Degraded by t' Matter?

Journal Article · Fri Dec 23 00:00:00 EST 2011 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3666627· OSTI ID:21612439

Arikawa, Mitsuhiro ^[1]; Aoki, Hideo ^[2]; Hatsugai, Yasuhiro ^[3]

---

1. Center for Computational Science, University of Tsukuba, Tsukuba, 305-8571 (Japan)
2. Department of Physics, University of Tokyo, Hongo, Tokyo 113-0033 (Japan)
3. Institute of Physics, University of Tsukuba, Tsukuba, 305-8571 (Japan)

While usual edge states in the quantum Hall effect reside between adjacent Landau levels, QHE in graphene has a peculiar edge mode at E = 0 that resides right within the n = 0 Landau level as protected by the chiral symmetry. In real graphene, small but finite second-neighbor hopping exists, which degrades the chiral symmetry in the bipartite lattice. Here we have found that the edge mode is again embedded in the n = 0 bulk Landau level despite the broken chiral symmetry due to the second-neighbor hopping, where the charge is accumulated along the zigzag edge. Hence the behavior of the zero mode has turned out to be distinguished from the case of zero magnetic field, which is related to the stability of topological compensation. This charge density accumulated along the zigzag edge can be measured with an STM imaging in magnetic fields.

• OSTI ID: 21612439
• Journal Information: AIP Conference Proceedings, Vol. 1399, Issue 1; Conference: 30. international conference on the physics of semiconductors, Seoul (Korea, Republic of), 25-30 Jul 2010; Other Information: DOI: 10.1063/1.3666627; (c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
36 MATERIALS SCIENCE
CARBON COMPOUNDS
CHARGE DENSITY
CHIRAL SYMMETRY
GRAPHITE
HALL EFFECT
MAGNETIC FIELDS
PHASE STABILITY
SCANNING TUNNELING MICROSCOPY
TOPOLOGY
CARBON
ELEMENTS
MATHEMATICS
MICROSCOPY
MINERALS
NONMETALS
STABILITY
SYMMETRY