Yb3+- and Er3+-doped Y2O3 microcrystals for upconversion photoluminescence and energy transfer with enhancements of near-ultraviolet emission

Yb3+ and Er3+ were doped into Y2O3 to form Y2O3: Yb3+, Er3+ microcrystals. The effect of doping concentration of Yb3+ was studied. The near-ultraviolet (UV) upconversion (UC) emission spectra of Y2O3: Yb3+, Er3+ were studied under 1.55-mu m excitation. The near-UV UC emissions centered at 391 and 418 nm were enhanced by Yb3+ under 1.55-mu m laser excitation. Er3+ generally acts as activator and is not used as sensitizer in the reference Er3+- doped oxides. In the present upconversion process under the 1.55-mu m laser excitation, the energy transfer from Er3+ to Yb3+ and then Yb3+ to Er3+ was observed. Dopant Er3+ acted as not only activator but also sensitizer. The energy transfer between Er3+ and Yb3+ enhanced the near-UV UC emission of our materials.

Automated summary

The doping concentrations of Yb3+ affect the UC emission of Y2O3, while Yb3+ can enhance the near-UV UC emission under 1.55-mu m excitation. Er3+ serves as both activator and sensitizer, and the energy transfer between Er3+ and Yb3+ enhances the near-UV UC emission of the materials.