Graphdiyne as a Promising Mid‐Infrared Nonlinear Optical Material for Ultrafast Photonics

Abstract Graphdiyne (GDY) is a novel 2D all‐carbon nanomaterial, which has an intransic band gap, strong light–matter interaction, and large optical absorption in the infrared region, indicating that it has great potential in the field of mid‐infrared ultrafast photonics. Here, a Z‐scan method is used to demonstrate the broadband and strong nonlinear optical (NLO) response of GDY, and its performance in the application of mid‐infrared ultrafast photonics is explored for the first time. The experimental results demonstrate that its nonlinear parameters are superior to the current mainstream 2D materials. By using GDY as the saturable absorber, stable mode‐locked and chaotic pulses are obtained at 1.5 µm. In addition, as a mode‐locked device of thulium‐doped fiber laser, high‐power pulse output is obtained at 2 µm band. This work shows that GDY, as a promising NLO material, has opened up a new pathway for the development of near‐ and mid‐infrared photonic devices.