The energy transfer dynamics between Yb3+ and Er3+ ions in Lithium niobate
is investigated after ytterbium-pulsed excitation at 920 nm. The sensitisat
ion of the LiNbO3: Er3+ system with Yb3+ ions does not modify the lifetime
of the I-4(13/2) erbium level(1.5-mu m emission), whereas it induces a mark
ed, concentration-dependent change in the lifetime of the F-2(5/2) (Yb3+) a
nd S-4(3/2) (Er3+) multiplets (1060-nm and 550-nm emissions, respectively).
The results are analysed by using the rate-equation formalism and cross-re
laxation model for the energy transfer.