• 文献标题:   Tilted anisotropic Dirac cones in quinoid-type graphene and alpha-(BEDT-TTF)(2)I-3
  • 文献类型:   Article
  • 作  者:   GOERBIG MO, FUCHS JN, MONTAMBAUX G, PIECHON F
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   1098-0121
  • 通讯作者地址:   Univ Paris 11
  • 被引频次:   197
  • DOI:   10.1103/PhysRevB.78.045415
  • 出版年:   2008

▎ 摘  要

We investigate a generalized two-dimensional Weyl Hamiltonian, which may describe the low-energy properties of mechanically deformed graphene and of the organic compound alpha-(BEDT-TTF)(2)I-3 [BEDT-TTF=bis(ethylenedithio)tetrathiafulvalene] under pressure. The associated dispersion has generically the form of tilted anisotropic Dirac cones. The tilt arises due to next-nearest-neighbor hopping when the Dirac points, where the valence band touches the conduction band, do not coincide with crystallographic high-symmetry points within the first Brillouin zone. Within a semiclassical treatment, we describe the formation of Landau levels in a strong magnetic field, the relativistic form of which is reminiscent of that of graphene, with a renormalized Fermi velocity due to the tilt of the Dirac cones. These relativistic Landau levels, experimentally accessible via spectroscopy or even a quantum-Hall-effect measurement, may be used as a direct experimental verification of Dirac cones in alpha-(BEDT-TTF)(2)I-3.