Fractional Quantum Hall States in Bilayer Graphene Probed by Transconductance Fluctuations
- Author(s)
- Youngwook Kim, Dong Su Lee, Suyong Jung, Viera Skakalova, T. Taniguchi, K. Watanabe, Jun Sung Kim, Jurgen H. Smet
- Abstract
We have investigated fractional quantum Hall (QH) states in Bernal-stacked bilayer graphene using transconductance fluctuation measurements. A variety of odd-denominator fractional QH states with ν
QH → ν
QH + 2 symmetry, as previously reported, are observed. However, surprising is that also particle-hole symmetric states are clearly resolved in the same measurement set. We attribute their emergence to the reversal of orbital states in the octet level scheme induced by a strong local charge imbalance, which can be captured by the transconductance fluctuations. Also the even-denominator fractional QH state at filling -1/2 is observed. However, contrary to a previous study on a suspended graphene layer [ Ki et al. Nano Lett. 2014, 14, 2135 ], the particle-hole symmetric state at filling 1/2 is detected as well. These observations suggest that the stability of both odd and even denominator fractional QH states is very sensitive to local transverse electric fields in bilayer graphene.
- Organisation(s)
- Department of East Asian Studies, Physics of Nanostructured Materials
- External organisation(s)
- Pohang University of Science and Technology (POSTECH), Max-Planck-Institut für Festkörperforschung, Korea Institute of Science and Technology (KIST), Korea Research Institute of Standards & Science (KRISS), Slovak University of Technology in Bratislava, Research and Services Division of Materials Data and Integrated System
- Journal
- Nano Letters: a journal dedicated to nanoscience and nanotechnology
- Volume
- 15
- Pages
- 7445-7451
- No. of pages
- 7
- ISSN
- 1530-6984
- DOI
- https://doi.org/10.1021/acs.nanolett.5b02876
- Publication date
- 11-2015
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103018 Materials physics
- Keywords
- ASJC Scopus subject areas
- Condensed Matter Physics, Mechanical Engineering, Bioengineering, Chemistry(all), Materials Science(all)
- Portal url
- https://ucris.univie.ac.at/portal/en/publications/fractional-quantum-hall-states-in-bilayer-graphene-probed-by-transconductance-fluctuations(7cff3f30-ad30-48b2-a9e1-080e719ee90f).html