We have prepared the graphene∕MoS_(2) heterostructure by a hydrothermal method,and presented its nonlinear absorption parameters and application as a nonlinear optical modulator in the mid-infrared region.Using the nonlinear optical modulator,stable passively Q-switched operation of an Er^(3+)-doped ZrF_(4)-BaF_(2)-LaF_(3)-AlF_(3)-NaF(ZBLAN)fiber laser at~2.8μm can be obtained.The Q-switched Er^(3+)-doped ZBLAN fiber laser can yield per-pulse energy up to 2.2μJ with the corresponding pulse width and pulse repetition rate of 1.9μs and 45 kHz,respectively.Our results indicate that the graphene∕MoS_(2) heterostructure can be a robust optical modulator for pulsed lasers in the mid-infrared spectral range.
