Amplified propagating plasmon in asymmetrical graphene periodic structure

Abstract

Abstract The excitation and amplification of the propagating plasmons in a periodic active (with population inversion of charge carriers) graphene-based structure with dual grating-gate with an asymmetric unit cell is studied theoretically. Such structure transforms the normally incident THz electromagnetic wave into sustained or amplified unidirectionally propagating plasmon. This effect is caused by simultaneous excitation of radiative and ‘non-radiative’ plasmon modes at the same frequency.