Y₂O₃:Er³⁺, Yb³⁺ nanoparticles are prepared by laser ablation on the oxide mixture.

Number of carbonate and hydroxyl groups in the nanoparticles is decreased.

These nanoparticles present improved emission properties.

For the first time, infrared emission at 1550 nm is almost suppressed.

Mechanisms are explained in terms of reduced nonradiative relaxation.