Broadband nonlinear optical response of graphdiyne for mid-infrared solid-state lasers

Graphdiyne (GDY), a novel all-carbon nanomaterial, is considered the most easily synthesized and stable carbon allotrope, positioning it as a promising photoelectric material. Herein, we successfully fabricated a high-quality GDY saturable absorber and saturable absorber mirror. Both broadband nonlinear saturable absorption and ultrafast relaxation dynamic properties in mid-infrared region of the GDY were investigated. All solid-state diode-pumped short and ultrashort pulsed lasers were realized using the GDY absorber at wavelengths of 2 and 2.8 µm, respectively. The results were then theoretically analyzed. This is the first presentation of ultrashort pulsed lasers in the mid-infrared region with GDY absorbers. These results resolutely confirm that GDY could be an optional broadband SA for all solid-state mid-infrared pulsed lasers, and they evidence its promising applications in mode-locked ultrafast lasers.