▎ 摘　　要

This work reports the optically induced transparency and extinction in MoS2, MoSe2, and graphene nanosheets in N-methyl-2-pyrrolidone. It is found that the 632.8 nm continuous-wave probe light can be effectively modulated by the 532 nm nanosecond pump pulsed laser into peaks (transparency) and valleys (extinction) induced by two distinct nonlinear optical mechanismssaturable absorption and nonlinear scattering, respectively. The optical modulation depths under different pump conditions have been deduced, and the maximum value of the modulation depth can reach approximate to 7 dB. Multiple nonlinear optical mechanisms coexisting in these 2D nanomaterials make them a category of intriguing and promising candidate materials for diverse photonic applications.