Nonlinear Optical Properties of Few‐Layer Rhenium Disulfide Nanosheets and Their Passively Q‐switched Laser Application

Abstract

Rhenium disulfide nanosheets (ReS 2 NSs) are attracting increasing attention because of their unique layer‐independent physicochemical properties, however, their nonlinear optical (NLO) properties are less investigated. Herein, ReS 2 NSs are successfully exfoliated by the sonication assisted liquid phase exfoliation method. Their broadband NLO responses are studied by open aperture and closed‐aperture Z‐scan technique at 532–1342 nm. The ReS 2 NSs dispersion exhibits saturable absorption, nonlinear scattering, and refraction responses. Broadband saturable absorption responses are also observed for the ReS 2 NSs film on the glass substrate. Additionally, two‐photon absorption response is shown at 1342 nm at larger excitation energy. The saturable absorption of ReS 2 NSs makes it possible to fabricate the saturable absorber with the as‐prepared nanosheets. Passively Q‐switched laser operations are realized at 1.06 and 1.3 µm. These results have revealed the potential of ReS 2 NSs in versatile NLO applications.