Title | Observation of an electric-field-induced band gap in bilayer graphene by infrared spectroscopy. |
Publication Type | Journal Article |
Year of Publication | 2009 |
Authors | Mak, KFai, Lui, CHung, Shan, J, Heinz, TF |
Journal | Phys Rev Lett |
Volume | 102 |
Issue | 25 |
Pagination | 256405 |
Date Published | 2009 Jun 26 |
ISSN | 0031-9007 |
Abstract | It has been predicted that application of a strong electric field perpendicular to the plane of bilayer graphene can induce a significant band gap. We have measured the optical conductivity of bilayer graphene with an efficient electrolyte top gate for a photon energy range of 0.2-0.7 eV. We see the emergence of new transitions as a band gap opens. A band gap approaching 200 meV is observed when an electric field approximately 1 V/nm is applied, inducing a carrier density of about 10(13) cm(-2)}. The magnitude of the band gap and the features observed in the infrared conductivity spectra are broadly compatible with calculations within a tight-binding model. |
DOI | 10.1103/PhysRevLett.102.256405 |
Alternate Journal | Phys. Rev. Lett. |
PubMed ID | 19659105 |