Electric‐Tunable Photoluminescence of 2D ErOCl for High‐Security Encryption of Programmable Information

Abstract High‐security encryption has always been important in economic and military fields as well as in daily life. 2D van der Waals (vdW) rare‐earth (RE) materials have advantages in photoluminescence (PL) modulation to achieve high‐security encryption because of their multiple sharp emission peaks, which will facilitate the multimode regulation for high‐security encryption of programmable information. Here, programmable information encryption has been achieved by applying 2D vdW ErOCl via the editable electric‐tunable PL. The correct information encoded in PL outputs can be tactfully decrypted from the PL intensity ratio of ²H_11/2–⁴I_15/2 and ⁴S_3/2–⁴I_15/2 transitions. This strategy for ASCII codes and images encryption with high‐security is demonstrated. This novel approach, PL modulation of 2D vdW RE material based on programmable electric inputs, will mark a new path to achieve high‐security encryption.