Spatiotemporal Self‐Encrypted Interlock‐Cascade‐Hashing Optical Storage Based on Multicolor Photochromic Lithographic Array

Continuing deve7lopments in artificial intelligence and quantum computing challenge the information security of physical assets and intellectual property. Photochromic materials have emerged as promising candidates for optical encryption and storage applications due to their intrinsic reversible, real-time light absorption modulation capability. Although all-inorganic devices exhibit pronounced stability and fatigue resistance, single-component multicolor photochromic systems remain exceedingly rare. Here, a multicolor photochromic phenomenon is reported in PbMoO₄ microcrystal, demonstrating both volatility and non-volatility through distinct photochromic channels. The input, output, and control signals of this material are all different wavelengths of light, which operate in an all-optical and non-destructive manner. Moreover, the all-solid-state nature of PbMoO₄ ensures its stable modulation capability after multiple photoresponse cycles with upconversion luminescence modulation up to 99%. By combining experimental characterizations with ab-initio molecular dynamics (AIMD) simulations, the mechanisms of each photochromic channel are revealed. Employing lithography and mask patterning, on-chip arrays are fabricated to demonstrate the feasibility of spatiotemporal self-encrypted optical information storage and interlock-cascade-hashing encryption. This work holds significant promise for advancing anti-cloning and anti-cracking technologies for high-value devices, assets, and information.