Energy levels, transitions glasses

Fig. 5. Energy level diagram and selected transitions of Nd,+ ions in fluoride glasses. ( ) Dv2, 2G9/2, 4Gn. 2- and "K-is/2 levels.

Gd3+ ion possesses high energy levels located in the UV. Absorption spectra of Gd3+-doped fluoride glasses show several peaks in the 240-320 nm range. They correspond to transitions from the 8S7/2 ground state to the 6P, 6I, and 6D excited states. Judd-Ofelt parameters and experimental lifetimes have been determined for Gd3+-doped fluorozirconate [34,141], and fluoroindate glasses [142], X-ray excitation of both glasses leads to radiative emission from all excited states 6P, 6I,... 

Figure 2. Energy level Scheme of Tm -Yb codoped oxyfluoride glass ceramic. The Dashed lines show the upconversion process to populate G4 level of Tm ions by eneigy transfer from Yb ions which are produced by using OPO laser at 975 nm. Solid line shows the optical gain transition.

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