ABSTRACT
Terahertz (THz) lasers on optically pumped multiple-graphenelayer (MGL) structures as their active region are proposed and evaluated. Optical excitation of graphene can result in the interband population inversion and negative real part of the dynamic conductivity of a graphene layer in the THz range of frequencies. In this chapter, the authors propose and evaluate the THz lasers based on MGL structures with a metal slot-line waveguide or a dielectric waveguide pumped by optical radiation. To maximize the THz gain at the desirable frequency, one needs carefully optimize the geometrical parameters. Considering the propagation of the THz electromagnetic wave in the laser structure and its reflection from edges or from the external mirrors. The authors propose THz lasers with optical pumping based on MGL structures with waveguides and calculated their characteristics. They demonstrate the feasibility of lasing in the devices under consideration at the low end of the THz frequency range at room temperatures.
