Influence of Li+ codoping on visible emission of Y2O3:Tb3+, Yb3+ phosphor

Comparison of the upconversion emission spectra of 0.1 mol% Tb3+ + 3.0 mol% Yb3+ and 0.1 mol% Tb3+ + 3.0 mol% Yb3+ + 2.0 mol% Li+ codoped Y2O3 phosphors.