The Upconversion Luminescence of Er3+/Yb3+/Nd3+ Triply-Doped β-NaYF₄ Nanocrystals under 808-nm Excitation.

The Upconversion Luminescence of Er3+/Yb3+/Nd3+ Triply-Doped β-NaYF₄ Nanocrystals under 808-nm Excitation.