Вид документа : Статья из журнала Шифр издания : 54/U 67 Автор(ы) : Leonidov I.I., Zubkov V.G., Tyutyunnik A. P., Tarakina N. V., Surat L. L., Koryakova O. V., Vovkotrub E. G. Заглавие : Upconversion luminescence in Er3+/Yb3+ codoped Y2CaGe4O12 [Electronic resource] Место публикации : Journal of Alloys and Compounds. - 2011. - Vol. 509, № 5. - С. 1339-1346 Систем. требования: http://www.sciencedirect.com/science/article/pii/S0925838810025600 Примечания : Bibliogr. : p. 1345-1346 (52 ref.) . - 13.10.2011 ББК : 54 Предметные рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: Calcium yttrium tetrametagermanates Y2CaGe4O12 doped with Er3+ and Er3+/Yb3+ reveal upconversion emission in visible spectral range under near-infrared excitation, ex = 980 nm. For the solid solution ErxY2?xCaGe4O12 concentration dependencies for the green and red lines of the visible emission around 526 nm (2H11/2 4I15/2), 545 nm (4S3/2 4I15/2) and 670 nm (4F9/2 4I15/2) show the optimal value for the sample x = 0.2. The power dependence of the visible luminescence measured at room temperature in the low-power limit indicates two-photon upconversion process. Direct intensification of the upconversion emission signals has been achieved by ytterbium sensitizing. The other upconversion excitation mechanism in Y2CaGe4O12:Er3+ is discussed for an 808 nm incident laser irradiation. A scheme of excitation and emission routes involving ground/excited state absorption, energy transfer upconversion, nonradiative multiphonon relaxation processes in trivalent lanthanide ions in Y2CaGe4O12:Er3+ and Y2CaGe4O12:Er3+, Yb3+ has been proposed. Conditions for visible emission occurrence under quasi-resonance ex = 1064 nm excitation depending on pump power values are considered. In the low-power regime only near-infrared emission caused by the transition 4I13/2 4I15/2 in erbium ions has been detected Держатели документа: Центральная научная библиотека УрО РАН Доп.точки доступа: Leonidov, I.I.; Zubkov, V.G.; Tyutyunnik, A. P.; Tarakina, N. V.; Surat, L. L.; Koryakova, O. V.; Корякова Ольга Васильевна; Vovkotrub, E. G.