980 nm-excited multiphoton photocarrier separation process of Yb3+ ions under Internal Electric Field and its upconverting modification on Eu3+ ions

Abstract In this work, we report a new optical properties and modification methods for the rare-earth (RE) ion doped upconversion (UC) materials. Here, The Yb3+- Eu3+ co-doped BiOCl layered micrometer crystals were synthesized via the traditional solid state reaction. The experiment results show that due to efficient photocarrier space separation role of IEF, a band-to-band multiphoton excitation process of Yb3+ ions and the subsequent photopolarization role have been triggered inside BiOCl crystals via a commercial 980 nm laser. Then, it combines the photopolarization electric field (PPF) of the laser beam to generate a multiplexed tunable photopolarization on the Eu3+ ions. Consequently, the uponverting Stark splitting and emission intensity ratio of electrical dipole transitions (EDTs) of Eu3+ ions could be tailored simultaneously, either by pumping power or Yb3+ ion doping level, but showing an opposite trend. This research provides new insights into the interaction between the light and materials as well as the UC tailored method of lanthanide ions, which may inspire the design of opto-electric multifunctional devices.