Glossary
Optical properties of rare-earth ions

ions de terres rares; rare-earth ions

Ions (generally trivalent) from the lanthanide series (Ce³⁺ to Yb³⁺) of Mendeleev's table.

crystal field; champ cristallin

Electrostatic field exerted by the ions surrounding the rare-earth ion in a solid material.

relaxation croisée; cross-relaxation

Energy transfer mechanism between two neighboring ions resulting in the excitation of a lower energy level than the one initially excited.

Addition de Photons par Transfert d'Énergie or APTE; energy transfer up-conversion

Energy transfer mechanism between two neighboring ions resulting in the excitation of a higher energy level than the one initially excited.