2009/10/31 by Tobias Stauber, T. Stauber, J. Schliemann +1 · 1 citation
Engineering · Materials Science · Mathematics · Physics and Astronomy · #Born approximation #Brillouin zone #Condensed matter physics #Dirac (video compression format) #Graphene #Graphene research and applications #Logarithm #Mathematical analysis #Mathematical physics #Mathematics #Omega #Physics #Plasmonic and Surface Plasmon Research #Polarizability #Quantum Electrodynamics and Casimir Effect #Quantum mechanics #Scattering #Singularity #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.81.085409
published as Phys. Rev. B 81, 085409 (2010) · 8 pages, 6 figures
openalex publication_date 2010/02/04 · arxiv created 2010/02/05 · arxiv updated 2010/02/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We compute the dynamical polarizability of graphene beyond the usual Dirac cone approximation, integrating over the full Brillouin zone. We find deviations at \ensuremathℏ\ensuremathω=2t (where t is the hopping parameter) which amount to a logarithmic singularity due to the Van Hove singularity and derive an approximate analytical expression. Also at low energies, we find deviations from the results obtained from the Dirac cone approximation which manifest themselves in a peak spitting at arbitrary direction of the incoming wave vector q. Consequences for the plasmon spectrum are discussed.