Dynamic color encryption controlled by lanthanide dual-mode luminescence emission and logistic mapping

Abstract

Rare earth luminescent materials with broad-wavelength responsiveness are ideal for optical encryption due to their tunable emission properties. When combined with algorithmic assistance, optical information can achieve intelligent feedback and highly secure encryption. In this work, NaYF₄ co-doped with y% Eu³⁺ ions and Er³⁺ ions is employed to achieve dual-mode luminescence tuning. Under 980 nm and 271 nm laser excitation, switchable orange-red and green luminescence outputs are achieved through electron transition processes. Furthermore, color coordinates are utilized for logistic mapping encryption, where confirmed parameter values generate the desired chaotic behavior, achieving high-capacity and high-complexity multiplexed key streams. The decryption process requires strict adherence to specific readout and iteration rules to access the encrypted information. Additionally, the excitation wavelength is introduced as a checkpoint to trigger decryption. This strategy of coupling logistic mapping with multi-mode luminescence broadens the avenues for efficient optical information encryption, while enhancing both the usability and security of the encryption method.