Cooperative dual-wavelength energy storage in self-powered perovskite NIR cryptodetectors

While optical encryption enhances data security, conventional single-wavelength protocols remain vulnerable to interception due to limited dynamic decryption capabilities. Here, we report a cooperative dual-wavelength (980/1550 nm) energy storage mechanism in Er³⁺, Tm³⁺ co-doped Cs₂NaYbCl₆ nanoparticles, achieving a 53.8-fold enhancement in red emission compared to single-wavelength excitation. Leveraging this synergy, we developed a self-powered photodetector (FTO/PEDOT: PSS/PVP-MAPbI_2.5Br_0.5/PCBM/Ag) featuring polyvinylpyrrolidone-induced defect states and an optimized halide composition (I^－/Br^－ = 5:1). This architecture enables wavelength-selective charge trapping, effectively restricting device activation to synchronized dual-wavelength inputs. By integrating time-domain multiplexing with wavelength selective thresholds, we implement AND-gate logic encryption, where 1550 nm radiation encodes the data and 980 nm serves as the decoding key. Compared to traditional single-wavelength systems, this dual-authentication protocol significantly enhances anti-interception capabilities and enables direct optical-domain key verification, eliminating the requirement for complex optoelectronic conversion modules or dedicated processing chips.