Upconversion photoluminescence properties of Ho3+/Yb3+ co-doped YNbO4 powder

Photoluminescence behavior of rare earth doped self-activated phosphors (i.e. niobate and vanadate) and their applications

“…3 shows the UC emission behavior of the rare earth (Ho 3+ /Yb 3+ and Tm 3+ /Yb 3+ ) doped YNbO 4 , GdNbO 4 and LaNbO 4 phosphors in the visible region on excitation with a 980 nm diode laser. 25,[28][29][30] Intense green and moderately weak red emissions are observed in the GdNbO 4 :Ho 3+ ,Yb 3+ phosphor, as shown in Fig. 3(a), in which optimization was performed to get intense UC emission by varying the concentrations of Ho 3+ and Yb 3+ ions, shown in the inset of the gure.…”

Highly sensitive response of luminescence chromaticity to laser power in Lu2Mo4O15:Yb3+/Ho3+ upconverting materials

“…Subsequently, the electrons that occupy this level decay to the lower 5 I 7 level with non-radiative relaxation, and then via another energy transfer from Yb 3+ to Ho 3+ are promoted to 5 F 5 , causing red UCL. 31 In contrast, there are two channels for the generation of green UCL: (1) part of the electrons at the 5 I 6 level jump to the 5 S 2 / 5 F 4 level under the sensitization of Yb 3+ , resulting in green UCL with a two-photon nature; 32 (2) some electrons at 5 S 2 / 5 F 4 and 5 F 5 levels continue to be pumped to a higher excited state, and then repopulate the 5 S 2 / 5 F 4 level through non-radiative relaxation, followed by the green emission with three-photon nature. 30,33 Fig.…”

Hydrothermal Synthesis, Structural Analysis and Photoluminescence Study of Nd3+/Ho3+ Doped Nanophosphors

“…In addition, Nd 3+ acts as a sensitizer by increasing the material's emission intensity of Ho 3+ ions. The upconversion emission spectra of room temperature GdPO 4 shows emissions from both Ho 3+ and Nd 3+ under near-infrared (IR) light at 808 nm [6][7][8][9][10] . By using an 808 nm laser to excite the sample, it is possible to analyse down-conversion, up-conversion, and energy transfer efficiency processes in detail.…”