V. U. Nazarov

Optics of Semiconductors from Meta-Generalized-Gradient-Approximation-Based Time-Dependent Density-Functional Theory

We calculate the optical spectra of silicon, germanium, and zinc blende semiconductors in the adiabatic time-dependent density-functional formalism, making use of kinetic energy density-dependent [meta-generalized-gradient-approximation (GGA)] exchange-correlation functionals. We find excellent agreement between theory and experiment. The success of the theory on this notoriously difficult problem is traced to the fact that the exchange-correlation kernel of meta-GGA supports a singularity of the form α/q(2) (where q is the wave vector and α is a constant), whereas previously employed approximations (e.g., local-density and generalized gradient approximations) do not. Thus, the use of the adiabatic meta-GGA opens a new path for handling the extreme nonlocality of the time-dependent exchange-correlation potential in solid-state systems.

Theory of acoustic surface plasmons

J. M. Pitarke,1,2 V. U. Nazarov,3 V. M. Silkin,2 E. V. Chulkov,2,4 E. Zaremba,5 and P. M. Echenique2,4 1Materia Kondentsatuaren Fisika Saila, Zientzi Fakultatea, Euskal Herriko Unibertsitatea, 644 Posta kutxatila, E-48080 Bilbo, Basque Country, Spain 2Donostia International Physics Center (DIPC) and Centro Mixto CSIC-UPV/EHU, Manuel de Lardizabal Pasealekua, E-20018 Donostia, Basque Country, Spain 3Department of Physics and Institute for Condensed Matter Theory, Chonnam National University, Gwangju 500-757, Korea 4Materialen Fisika Saila, Kimika Fakultatea, Euskal Herriko Unibertsitatea, 1072 Posta kutxatila, E-20080 Donostia, Basque Country, Spain 5Department of Physics, Queen’s University, Kingston, Ontario, Canada K7L 3N6 (Received 2 June 2004; published 4 November 2004)

Symmetry classification of energy bands in graphene

We present the results of the first principle calculations of the energy bands in graphene and their symmetry classification. The valence bands and four lowest conduction bands are classified according to their symmetry at the points

Including nonlocality in the exchange-correlation kernel from time-dependent current density functional theory: Application to the stopping power of electron liquids

\Gamma

Scattering resonances in two-dimensional crystals with application to graphene

and

Resolving the wave vector and the refractive index from the coefficient of reflectance

K

Time-dependent density-functional theory for the stopping power of an interacting electron gas for slow ions

. Merging of the bands is interpreted in the framework of the group theory.

Nanostructured metamaterials with broadband optical properties

We develop a scheme for building the scalar exchange-correlation (XC) kernel of time-dependent density functional theory (TDDFT) from the tensorial kernel of time-dependent current density functional theory (TDCDFT) and the Kohn-Sham current density response function. Resorting to the local approximation to the kernel of TDCDFT results in a nonlocal approximation to the kernel of TDDFT, which is free of the contradictions that plague the standard local density approximation (LDA) to TDDFT. As an application of this general scheme, we calculate the dynamical XC contribution to the stopping power of electron liquids for slow ions to find that our results are in considerably better agreement with experiment than those obtained using TDDFT in the conventional LDA.

Dynamical many-body corrections to the residual resistivity of metals

E. E. Krasovskii and V. M. Silkin Departamento de F́ısica de Materiales, Facultad de Ciencias Qúıimicas, Universidad del Pais Vasco/Euskal Herriko Unibertsitatea, Apdo. 1072, San Sebastián/Donostia, 20080 Basque Country, Spain Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, San Sebastián/Donostia, 20018 Basque Country, Spain and IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain

Electronic excitations in quasi-2D crystals: what theoretical quantities are relevant to experiment?

We resolve the existing controversy concerning the selection of the sign of the normal-to-the-interface component of the wave vector k(z) of an electromagnetic wave in an active (gain) medium. Our method exploits the fact that no ambiguity exists in the case of a film of the active medium, since its coefficient of reflectance is invariant under the inversion of the sign of k(z). Then we show that the limit of the infinite film thickness determines a unique and physically consistent choice of the wave vector and the refractive index. Important practical implications of the theory are identified and discussed.