Group‐IV monochalcogenide ferroelectric materials possess fascinating nonlinear optical properties and electro‐optical effects which play a vital role in 2D ferroelectrics, multiferroics and nonlinear optoelectronics. However, the studies of nonlinear optical properties of group‐IV monochalcogenides are still in their infancy stage. Herein, the preparation of few‐layer SnS by the molecular beam epitaxy (MBE) method is reported and the efficient second harmonic generation (SHG) of SnS monochalcogenide is systematically scrutinized by using ultrafast nonlinear optical spectroscopy. The obtained thickness‐dependent SHG is highly related with the coherence length. Second‐order nonlinear susceptibility of few‐layer SnS is also obtained. Polarization‐dependent SHG studies reveal its intrinsic anisotropy pattern and can be utilized to identify the crystalline orientation of few‐layer SnS film.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.