A new class of upconversion luminescence tuning materials based on non-photochromic reaction: Er3+-activated Ba0.7Sr0.3Nb2O6 ferroelectrics

Abstract The upconversion (UC) luminescence tuning of phosphors has attracted increasing interest as optical switches, optical sensing, and high-density optical data storage devices. However, the design and synthesis of photo-switchable inorganic luminescent materials were still at primary stage. In this work, a new type of UC luminescence regulation materials, Er3+-activated tetragonal tungsten bronze Ba0.7Sr0.3Nb2O6 ferroelectrics, showing strong susceptibility to visible light irradiation, was reported based on non-photochromic (N-PC) effect. Under visible light irradiation, the maximum luminescent modulation ability reached up to 79.4%. The tuning of UC luminescence was disclosed to tightly rely on the irradiation time and thermal treatment processes. Meanwhile, excellent reproducibility was also demonstrated. Besides, the luminescent readout almost had no any influence on the UC emission, indicating the extremely low destruction to the stored luminescent states. The mechanisms related to the UC luminescence and manipulation were also discussed. In contrast to the previous tuning way based on PC reaction, it is believed that this work shed new light for the understanding of UC modulation fundamentals.