4 documents found, page 1 of 1
Effective Medium Model for Graphene Superlattices with Electrostatic and Magnet...
Fernandes, David E.30 pages, 6 figures; In this article we develop an effective medium model to characterize the electron wave propagation in graphene based nanostructures with an electrostatic and magnetic vector potentials imposed on their surface. We use a numerical algorithm to determine the effective medium parameters of the heterostructure and calculate the electronic band structure of the system. We apply our formalism to ...
Experimental verification of magnetic near-field channeling using a helical-sha...
Morgado, Tiago A.; João, Guilherme; Pereira, Ricardo A. M.; Fernandes, David E.; Lannebère, SylvainThis article was published in Applied Physics Letters; We experimentally verify that a magnetic uniaxial wire medium lens consisting of a racemic array of helical-shaped metallic wires may enable channeling the normal component of the magnetic field of near-field sources with resolution well below the diffraction limit over a broad bandwidth. It is experimentally demonstrated that the helical-shaped wire medium...
Time Evolution of Electron Waves in Graphene Superlattices
Fernandes, David E.; Rodrigues, Manuel; Falcão, Gabriel; Silveirinha, Mário G.preprint, 37 pages, 11 figures; The time evolution of electron waves in graphene superlattices is studied using both microscopic and 'effective medium' formalisms. The numerical simulations reveal that in a wide range of physical scenarios it is possible to neglect the granularity of the superlattice and characterize the electron transport using a simple effective Hamiltonian. It is verified that as general rul...
Analytical solution for the stopping power of the Cherenkov radiation in a unia...
Morgado, Tiago A.; Fernandes, David E.; Silveirinha, MárioThis article was published in Photonics 2015, 2(2), 702-718; We derive closed analytical formulae for the power emitted by moving charged particles in a uniaxial wire medium by means of an eigenfunction expansion. Our analytical expressions demonstrate that in the absence of material dispersion the stopping power of the uniaxial wire medium is proportional to the charges velocity, and that there is no velocity ...