ABSTRACT
This chapter analyzes a graphene tunneling transit-time device based on a heterostructure with a lateral p-i-n junction electrically induced in the graphene layer and calculate its ac characteristics. It shows that the ballistic transit of electrons and holes generated due to interband tunneling in the i-section results in the negative ac conductance in the terahertz frequency range. The chapter considers a tunneling transit-time device based on a gated graphene with electrically induced lateral p-i-n junction and present the device dynamic characteristics, the frequency dependences of the real and imaginary parts of the ac conductance, calculated using the developed device model. It also shows that the graphene tunneling transit-time can exhibit negative ac conductance in the terahertz (THz) range of frequencies and, hence, serve as an active element in THz oscillators. The generation of THz radiation is also possible due to the self-excitation of the plasma oscillations in the device p- and n-sections.
