ABSTRACT
In this chapter, the authors propose the concept of terahertz and infrared photodetectors using the resonant radiative transitions between graphene layers (GLs) in double-GL structures. They compare the photodetector responsivity with that of the GL p-i-n photodiodes and quantum-well infrared photodetectors. The bias voltage is applied between the pertinent contacts. These structures are similar to those recently fabricated. The grating gate period and the gate layer thickness should be optimized to maximize the radiation coupling and limit the spatial periodicity of the carrier (electron) density in the top GL. The authors evaluate the responsivity of the proposed double-GL photodetectors (DGL-PDs) and demonstrate that the DGL-PD responsivity as a function of the photon energy can exhibit the voltage tunable resonant maxima in a wide spectral range. They provide the possibility of implementing of effective DGL-PDs competitive with other THz and IR photodetectors, especially at elevated (room) temperatures.
