Fig. 1: Design principle and application of direct photo-patterning technique.
a Schematic diagram and photonic pattern based on direct photo-patterning technique. Self-erasure of pattern information simultaneously occurs with the read information. T1, T2, and T3 represent different times of the direct photo-patterning process, T1 < T2 < T3. b The universal pattern fabrication of direct photo-patterning technique for different perovskite compositions, shapes, and sizes. The yellow and crimson background photoluminescence colors correspond to binary mix-halide three-dimensional (3D) and two-dimensional (2D) perovskite films, respectively. c The importance of information transmission security. The main information transmission methods currently include letters, computers, mobile phones, and other types of wireless transmission devices. The real information of the quick response (QR) code is the letters “ZZU”. d Mechanism diagram of direct photo-patterning technique by pattern-controlled ion migration and photodegradation of the iodine-rich regions within mix-halide perovskite films. The red and green octahedra represent MAPbI3 and MAPbBr3 perovskites, respectively. The octahedra with other colors represent mixed bromine-iodine perovskites. e Schematic diagram of photonic pattern encryption and multilevel pattern encoding based on direct photo-printing technique. f Neural network-assisted information decryption. Neural network simulation enables highly accurate recognition of the encrypted pattern sizes corresponding to different binary codes, thus decrypting the information.
