Great enhancement of near band-edge emission of ZnSe two-dimensional complex nanostructures fabricated by the interference of three femtosecond laser beams

By using the method of the interference of three 800 nm femtosecond laser beams, we fabricated complex 2-dimensional (2D) micro/nanostructures on ZnSe crystal. Compared with the plane surface of ZnSe crystal, 2D nanostructures exhibit a great enhancement of near band-edge (NBE) emission and a compression of second harmonic generation (SHG) under excitation of infrared (IR) femtosecond laser with central wavelengths ranging from 1200 to 1600 nm. We studied the photoluminescence properties of 2D nanostructures and the mechanism of the enhancement of NBE emission. Our results indicated that the enhancement of NBE emission is caused by a combination of several processes including the increase in optical absorption, and the reabsorption of SHG by the nanostructures.