The graphene based terahertz transistor

Background and Objectives: Due to the lack of a substantial energy gap in graphene nanoribbons there are difficulties to create a fast-switching transistors for digital circuits using them. In a number of recent works, the usage of graphene nanoribbons in tunneling transistors, field effect transistors, transistors with negative resistance and in generators with pumping has been proposed for amplification of analog signals. Model and Methods: We consider the transistor with three electrodes, which connected by graphene nanoribbons or metal quantum wires working on the principle of current control by changing the voltage on the central electrode (the gate). The consideration is conducted within the framework of the Landauer–Datta–Lundstrom model in the approximation of equilibrium at the electrodes. This device works on the principle of controlling the current by changing the voltage on the gate, on which the Coulomb blockade can occur. The linear models have been considered and obtained as well as the nonlinear terms in the total current. We also consider and calculate the nonlinear currentvoltage characteristics of graphene nanoribbons. Results: The parameters of transistor amplifier which made as microstrip and slot-line realizations are considered taking into account the ballistic transport, ballistic inductance and capacitance of the electrodes. The gain of the voltage has been obtained. To increase them we propose to use between the source and the gate the nanoribbon, which wider and shorter as compared with nanoribbon between the gate and the drain.