Energy Transfer In Glasses Research Articles

On the kinetics of nonradiative energy transfer in Yb — Er phosphate glasses excited by a diode laser

The luminescence of a Yb — Er phosphate glass excited by a diode laser is studied as a function of the density of energy absorbed by a sample and the pump radiation intensity. An abrupt change in the depopulation rate of the Yb3+(2F5/2) level was observed after switching off the pump laser. This effect is explained qualitatively based on the kinetics of nonradiative energy transfer in glasses and crystals.

Localized-phonon assisted energy transfer in glasses

Abstract The disorder characteristic of glasses leads to weak localization of phonons whose ‘wavelengths’ are short compared to the range of density fluctuations in these materials. Results for the rate of phonon-assisted energy transfer due to these localized modes are presented. Two models are used as paradigms of phonon localization: fractons, in which the localization length is many interatomic distances, and Einstein modes, in which the each atom is an independent oscillator. In both cases the energy transfer rate exhibits regularly spaced peaks in the frequency domain, the spacing of the peaks corresponding to the low frequency mobility edge for the phonons localization. The physical reasons for this effect are discussed. Time-resolved site-selection spectroscopy of a series of glasses studied by Gang and Powell also shows regularly spaced peaks with spacings between 12 and 20 cm -1 . A detailed comparison with one of these suggests that energy transfer mediated by localized phonons may be responsible for the experimentally observed structure.

Nd 3+ → Yb 3+ energy transfer in glasses with composition close to LiLnP 4O 12 metaphosphate (Ln = La, Nd, Yb)

In the course of an investigation of new luminescent solar concentrators (LSC) we report a kinetic stúdy of the Nd 3+ → Yb 3+ energy transfer for Yb doped glasses with compositions close to LiLnP 4O 12 (Ln = La, Nd, Yb). If the only doping ion present is neodymium, the glasses exhibit low self quenching of the Nd 4F 3/2→ 4I 11/2 emission. For Nd 3+-Yb 3+ codoped glasses, the energy migration over the donor array can be explained by a hopping mechanism. Supermigration arises for neodymium concentrations exceeding 2.8 × 10 21 ions cm -3. The large ytterbium lifetime limits the neodymium decay rate at low ytterbium concentration.

Coherence and Energy Transfer in Glasses

"Coherence and Energy Transfer in Glasses." Optica Acta: International Journal of Optics, 33(7), p. 823

Influence of the segregation of the activator upon the energy transfer in glasses

Influence of the segregation of the activator upon the energy transfer in glasses