Nd → Yb energy transfer in (Nd, Yb):Y2O3 transparent ceramics

In the attempt to obtain new efficient laser systems, the Nd → Yb energy transfer characteristics in Y2O3 transparent ceramics were investigated. The spectral characteristics that assure the efficient resonant Nd3+ → Yb3+ energy transfer are presented, especially the overlap integral of the Nd3+4F3/2 → 4I9/2 emission with the Yb3+2F7/2 → 2F5/2 absorption in (Nd, Yb):Y2O3. The static spectral data reveal that the Nd3+ → Yb3+ energy transfer shows: a strong dependence on Yb3+ content (less on Nd3+), a small variation with temperature and the implication of both Yb3+ sites in transfer, though only Nd3+ in C2 are active. From the analysis of Nd3+4F3/2 emission decays in double doped samples it is concluded that the Nd → Yb transfer for Nd ∼1 at.% is of direct type, through the dipole–dipole interaction with global energy transfer microparameter ∼CDA,Nd–YbCDA,Nd–Yb ≈ 1 × 10−38 cm6 s−1 and transfer efficiencies up to 98% for rather low (∼5 at.%) Yb3+ content.