Enhanced nonlinear optical limiting in TiS_2 dichalcogenide 2D Sheets

摘要

Two dimensional (2D) graphene and transition metal dichalcogenides are an emerging class of extremely interesting materials showing unique physical properties, such as large third-order optical nonlinearity, offering potential applications in optical limiting. Here we report the optical limiting properties of Titanium disufide (TiS_2), and Graphene sheets measured using open aperture and photo-acoustic z-scan techniques. Our best results were observed in TiS_2sheets, yielding an optical limiting of 77% at an irradiance of 0.713 GW/cm~2with 2PA and 3PA absorption coefficient to be 80cm/GW and 2000 cm~3/GW~2 respectively. Also, TiS_2 sheets show improved shelf life and stability upon irradiation with higher laser powers. This demonstrates the feasibility of using them as a potential candidate for optical limiting applications.