A transmission line model for plasmon propagation on a graphene strip

We present a transmission line model for TM plasmon propagation along a graphene strip, and derive closed-form expressions for the kinetic and Faraday inductance, resistance, and electrostatic capacitance of the equivalent circuit as a function of graphene conductivity. The proposed approach also allows to analytically obtain the complex characteristic impedance of the line. The behavior of the circuital lumped elements and characteristic impedance is analyzed in connection with graphene properties. Results demonstrate that graphene-based strips present an extremely large characteristic impedance controlled by the width of the strip, which might be interesting for direct matching with photomixers in the terahertz band.