Terahertz emission and detection in double-graphene-layer structures

The authors discuss the photon-assisted resonant radiative intergraphene layer transitions for applications of double-graphene-layer (D-GL) heterostructures for THz/IR lasers and photodetectors (PDs). The main element of both lasers and PDs under consideration is a D-GL core-shell heterostructure with the independently contacted GLs separated by the thin transparent tunnel-barrier layer. The bias voltage applied between the GL's contacts induces the electron and hole gases in the opposing GLs. The electron and hole densities in GLs are controlled by the gate voltage.