The nonlinear optical properties of few-layer VSe2 nanosheets

Vanadium Diselenide (VSe2) has a high electrical conductivity owing to the electron delocalization of the vanadium lattice framework. Most of previous research has been focused on its electronic properties. The nonlinear optical properties of VSe2 have not been investigated yet. Herein, we prepared few-layer VSe2 nanoflakes by liquid phase exfoliation. Subsequently, we utilized Z-scan technique to study the nonlinear optical properties of few-layer VSe2 nanoflakes. And we prepared VSe2 based saturable absorbers (SA) and achieved passively mode-locked operation in Er-doped fiber laser. The results indicate that VSe2 nanosheets own remarkable nonlinear optical properties and could be employed as ideal saturable absorption materials in pulsed fiber lasers.