Energy transfer from Eu3+→Ho3+ in calibo glass

Study of energy transfer from optically excited Eu3+→Ho3+ has been carried out in calibo glass. Probabilities and efficiencies of energy transfer from Eu3+→Ho3+ have been calculated from the life time and emission intensity of Eu3++Ho3+. At low acceptor concentrations Psub(da) varies linearly with Csub(a) showing migration of energy among donors. At high acceptor concentrations Psub(da) depends linearly on (Csub(a)+Csub(d))2, which is inconsistent with Fong and Diestler's theory of dipole-dipole mechanism of energy transfer. At low temperature emission intensity and life time increase, decreasing probability (Psub(d)) and efficiency (etaT) suggesting at room temperature the energy is transferred to the lattice by donor lowering life time and intensity. At high temperature no emission from higher levels of the donor is obtained suggesting blurred energy levels in the glass matrix. (Auth.)