Broadband γ-graphyne saturable absorber for Q-switched solid-state laser

gamma-graphyne, a two-dimensional carbon material, has attracted much attention due to its unique characteristics, such as high carrier mobility and high stability. In the present study, a gamma-graphyne saturable absorber (SA) was fabricated and characterized. The linear optical absorption in the spectral range from the visible to mid-infrared as well as the nonlinear optical character of the SA were investigated. Passively Q-switched solid-state lasers emitting at 639 nm, 1342 nm and 1932 nm were realized using the gamma-graphyne SA. The results indicate that gamma-graphyne could be a promising alternative to the rare broadband optical modulator. (C) 2019 The Japan Society of Applied Physics