Graphene-Based Terahertz Waveguide Amplifier

Graphene has been considered as an ideal material for electronic applications because of its high carrier mobility and thermal properties. Here, we study the conductivity of graphene at terahertz (THz) frequency range. Light can tune the conductivity of graphene and it has been shown that optically pumped multiple graphene layer (MGL) presents negative conductivity in THz region due to inter-band population inversion. With use of this property THz travelling-wave amplifier based on optically pumped MGL has been introduced in this article. The gain characteristics of the amplifier at room-temperature have been obtained as a function of graphene layers and the Fermi level of layers. The obtained results are promising for next generation THz communications.