2008/03/31 by M. O. Goerbig, Jean-Noël Fuchs, J. -N. Fuchs +4 · 2 citations
Materials Science · Physics and Astronomy · #Graphene research and applications #Organic and Molecular Conductors Research #Quantum and electron transport phenomena #cond-mat.mes-hall #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.78.045415
published as Phys. Rev. B 78, 045415 (2008) · 11 pages, 5 figures; version accepted for publication in PRB, contains a more detailed discussion of the zero-energy Landau level in the presence of the tilt, technical parts shifted to the appendix
arxiv created 2008/06/20 · openalex publication_date 2008/07/15 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We investigate a generalized two-dimensional Weyl Hamiltonian, which may describe the low-energy properties of mechanically deformed graphene and of the organic compound \ensuremathα\text\ensuremath-(BEDT-TTF)2I3 [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 \ensuremathα\text\ensuremath-(BEDT-TTF)2I3.