Stimuli‐Responsive Lanthanide Activated Piezoelectric LiNbO3 Microcrystals for Multimode Luminescence and Optical Sensing Applications

Multimode luminescence is usually stimulated by various external stimuli in response to photon emission and is applied in various anti‐counterfeiting and encryption fields. However, integrating multimode luminescence into a single stable material, and how to quantitatively evaluate the relationship between temperature light and force light remains a challenge. In this work, LiNbO3:Er3+/Pr3+ microcrystals that can respond to X‐ray, UV light, temperature, and stress stimuli are developed. The temperature‐dependent upconversion emission spectra show a maximum relative sensitivity of 0.889% K−1 based on the intensity ratio. Meanwhile, the mechanoluminescence around 618 nm with a linear relationship is observed with the increase of force. These materials illustrate strong static and dynamic luminescence that can be manipulated in space and time dimensions, which provides new ideas in the field of anti‐counterfeiting and information encryption. Multimode luminescence from lanthanide‐activated piezoelectric lithium niobate (LiNbO3) microcrystals are realized by manipulating photonic emissions. The smart luminescent materials can respond to X‐ray, UV light, temperature, and stress stimuli. The dynamic manipulation of luminescence manifestations in time and space provides new ideas for anti‐counterfeiting and optical sensing applications.