The optical amplification of LiNbO3:Er3+/Yb3+ channel waveguides has been m
odelled in the small signal regime using the overlapping integrals method a
nd the rate-equation formalism. It has been found that Yb3+-sensitisation i
mproves the pump efficiency at 980 nm and a higher gain is achievable in th
e high power-limit compared to singly-doped LiNbO3:Er3+ amplifiers.