A dynamically-tunable graphene-based fano metasurface

Abstract

A planar graphene metasurface with rectangular holes, which is capable of supporting a dynamically tunable Fano resonance at Terahertz (THz) frequencies, is proposed. The rectangular hole is patterned asymmetrically within the metasurface's unit cell to 'brighten' an originally-dark quadrupolar surface plasmon mode. Fano resonance is achieved via the destructive interference of this mode with a dipolar surface plasmon. The spectral location and line shape of the Fano resonance can be dynamically tuned via a gate voltage applied to the metasurface to change graphene's optical properties. The dynamic tunability of the Fano resonance suggests the applicability of the proposed metasurface in designing THz wave modulators and band-pass filters. © 2013 IEEE.