▎ 摘　　要

The giant amplification and lasing of terahertz radiation due to stimulated generation of plasmons in graphene with a distributed planar Bragg resonator strongly coupled to THz radiation are predicted. The amplification of terahertz waves at the plasmon resonance frequencies is several orders of magnitude stronger than it is away from the resonances. The lasing at the plasmon resonance is achieved when the net plasmon gain in graphene approaches the negative of the radiative damping of the resonant plasmons, which ensures high plasmon coherence and self-excitation of a collective plasmon mode. It is shown that the dynamic and frequency ranges as well as the energy conversion efficiency of the terahertz graphene amplifier can be strongly enhanced in the structure with a narrow-slit Bragg grating and/ or thin barrier layer.