Complex Mode Spectra of Graphene-Based Planar Structures for THz Applications

Walter Fuscaldo (1, 2) , P. Burghignoli (2) , P. Baccarelli (2) , A. Galli (2)

1 IETR - Institut d'Électronique et des Technologies du numéRique
2 DIET - Dipartimento di Ingegneria dell'Informazione, Elettronica e Telecomunicazioni [Roma]

In this work we analyze in detail the modal properties of a graphene-based planar waveguide (GPW) in the THz frequency range. The structure consists of a graphene sheet placed on top of a grounded dielectric slab. As is known, the surface conductivity of the graphene sheet can easily be tuned with a bias voltage via electric-field effect; we show here how such a bias affects the propagation features of both TM and TE modes supported by the GPW. An extensive dispersion analysis is performed for complex modes in both guided and radiative (leaky) regimes, considering also dielectric and metal losses as well as nonlocal effects in graphene. In particular, we focus on the behavior of the fundamental leaky modes since they exhibit quite interesting radiation features for suitable values of the bias. These results are very promising for the development of reconfig-urable leaky-wave Fabry-Perot cavity antennas based on graphene at THz frequencies.

Mots clés: Graphene; Terahertz; Planar waveguides; Fabry-Perot cavity antennas; Surface waves; Leaky waves; Dispersion analysis

Domaines: Réseaux et télécommunications [cs.NI]

Walter Fuscaldo, P. Burghignoli, P. Baccarelli, A. Galli. Complex Mode Spectra of Graphene-Based Planar Structures for THz Applications. Journal of Infrared, Millimeter and Terahertz Waves, 2015, 36 (8), pp.720-733. ⟨10.1007/s10762-015-0178-0⟩. ⟨hal-01165595⟩