Femtosecond laser direct writing of CsPb(I/Br)₃ quantum dot films for displays and holography

To expand the application of perovskite quantum dots (QDs) in next-generation displays and holography, it is quite significant to develop an efficient and advanced QD patterning technology. Herein, we report the femtosecond laser direct writing of perovskite QDs for patterning holograms. Femtosecond laser scanning helps remove the surfactants of perovskite QDs and subsequently changes the solubility of perovskite QDs in a nonpolar solvent. Experimentally, perovskite QD gratings with a minimum line width of 565 nm were achieved. Using a programmable laser direct writing (LDW) system and an optical setup design, a micro-scale (300 × 300 μm) QD display and hologram are demonstrated, which provide great potential for microscopic three-dimensional displays.