Down-and up-conversion processes in Nd^(3+)/Yb^(3+)co-doped sodium calcium silicate glasses with concomitant Yb^(2+)assessment

作     者：R.F.Muniz V.S.Zanuto M.S.Gibin J.V.Gunha A.Novatski J.H.Rohling A.N.Medina M.L.Baesso R.F.Muniz;V.S.Zanuto;M.S.Gibin;J.V.Gunha;A.Novatski;J.H.Rohling;A.N.Medina;M.L.Baesso

作者机构：Departament of ScienceState University of MaringáAv.Reitor Zeferino Vaz s/nGoioerê87360-000PRBrazil Departament of PhysicsState University of MaringáAv.Colombo 5790Maringá87020-900PRBrazil Departament of PhysicsState University of Ponta GrossaAv.Carlos Cavalcanti4748Ponta Grossa 84030-900PRBrazil 

出 版 物：《Journal of Rare Earths》 (稀土学报（英文版）)

年 卷 期：2023年第41卷第3期

页      面：342-348,I0001页

核心收录：

学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0703[理学-化学] 0702[理学-物理学] 

主　　题：Solar cells Energy transfer Glassy systems Rare earths 

摘      要：Novel Nd^(3+)/Yb^(3+)co-doped sodium calcium silicate glasses were prepared by melting quenching method:Spectroscopic study was carried out as a function of doping content by fixing sensitizer(Nd^(3+))concentration to 0.2 mol%and adjusting activator(Yb^(3+))from 0 to 1.0 mol%.The energy transfer(ET)mechanisms between Nd^(3+)and Yb^(3+)are discussed based on their energy levels and excitation powerdependence emission *** show that the presence of Yb^(2+)might be considered for the Nd^(3+)-free and co-doped *** ET was confirmed by the down-conversion NIR emission spectra of the doped and co-doped samples under excitation at 808 *** mechanisms observed seem to involve only one VIS absorbed photon for each NIR emitted via direct energy transfer between^(4)F_(3/2)of Nd^(2+)and^(2)F_(5/2)of Yb^(3+)compensated by phonon assistance due to energy gap between these *** efficiency of ET increases with the ytterbium content up to almost 90%for the sample with 1 mol%of Yb2O3,which was evaluated by lifetime ***-conversion photoluminescence by exciting trivalent ions of neodymium(808 nm)and ytterbium(975 nm)is *** observed up-converted emission bands are related to the 4f-4f transitions of Nd^(3+)and the spin-forbidden 5d-4f transition of Yb^(2+).Nd^(3+)upconversion emission is observed under 975 nm excitation,presenting an almost quadratic emission dependence with power excitation,which suggests that two laser photons participate in the up-conversion(UC)process,showing that ET occurs by a phonon-assisted energy transfer and cooperative energy transfer.