Ultrafast optical nonlinearity in natural van der Waals heterostructure nanosheets of franckeite
Franckeite, a natural van p3221d der Waals heterostructure with excellent physicochemical characteristics, has shown great potential for high-performance optoelectronic device.Here, the few-layer franckeite nanosheets have been prepared by liquid phase-exfoliation method successfully, and the nonlinear optical absorption and copyright dynamics beha