Laser thinning induced the tunable of nonlinear optical property of MoS2 thin film

Abstract

In this paper, a series of MoS2 films with various thicknesses were fabricated by laser ablation technique at ambient conditions. The influences of thickness on the optical properties and structure of MoS2 films were investigated. X-ray diffraction (XRD) results show that the diffraction intensity firstly increased and then decreased with the decrease of thickness. The band gap of samples increased with the decrease of thickness. The plasmonic absorption peaks in the range of 250 nm–320 nm show a red-shift and then a blue ones with the thickness decreasing. With the decrease of thickness, the nonlinear absorption performance of the samples reduced with saturation absorption and then turned to reverse saturation absorption.