Fig. 1. Optic transmittance of BEuT (x = 0.85) thin films annealed at different temperatures^[24].

Fig. 2. Excitation and emission spectra of BEuT (x = 0.85) thin films annealed at different temperatures^[24].

Fig. 3. Photoluminescence spectra of BEuT thin films with different Eu³⁺ concentrations^[24].

Fig. 4. Emission spectra of BEGT and BEuT thin films under exciting wavelength of 350 nm^[26].

Fig. 5. Up-conversion emission spectra of Bi_3.98-xHo_0.02Yb_xTi₃O₁₂ thin films on fused silica substrates^[31]. The inset shows a photograph of the bright up-conversion green emission of Bi_3.78Ho_0.02Yb_0.2Ti₃O₁₂ thin films excited by 980 nm diode laser.

Fig. 6. Simplified energy level diagram for up-conversion emission of Ho/Yb-codoped bismuth titanate thin films^[31].

Fig. 7. P-E hysteresis loop of Bi_3.79Tm_0.01Yb_0.2Ti_2.99W_0.01O₁₂ thin films^[32].

Fig. 8. (a) Emission spectra excited at 350 nm UV radiation, and (b) 611 nm red emission intensity as a function of KBT content for Pr³⁺-doped x(K_1/2Bi_1/2)TiO₃-(1－x) (Na_1/2Bi_1/2)TiO₃ thin films^[33]. The inset of (b) shows a photoluminescence photograph of the thin film (x = 0.15).

Fig. 9. Emission spectra of (a) nanocomposite film composed of BEuT matrix and highly c-axis oriented ZnO nanorods and (b) BEuT thin film^[40].