▎ 摘　　要

We theoretically investigate the second-harmonic generation and photon drag effect induced by an incident plane wave to a doped graphene placed on a two-dimensional diffraction grating. The relevant nonlinear conductivity of the graphene is obtained by a semiclassical treatment with a phenomenological relaxation. The grating acts not only as a plasmon coupler, but also as a dispersion modulator of the graphene plasmon. As a result, the second-harmonic generation is strongly enhanced by exciting the graphene plasmon polariton of the first-and/or second-harmonic frequencies. The photon drag effect is also strongly enhanced by the excitation of the plasmon at the first-harmonic frequency. The direct current induced by the photon drag effect flows in both forward and backward directions to the incident light, depending on the modulated plasmon mode concerned. (C) 2017 Optical Society of America