U3+ DOPED FLUORIDE GLASS EMISSION AT 2.5-MU-M

Fluorescence dynamics of trivalent uranium in ZBLAN or BATY glasses an d ZBLAN fiber has been investigated at various temperatures. A careful l fluorescence analysis of all these systems allows to identify some o f the crystal field components of the ground level J--9/2. Fluorescenc e decays of the 2.5mum emission have been recorded using an infrared n anosecond pulsed laser indicating an average lifetime of hundred of mi lliseconds at low concentration. The non exponential behavior of the d ecay increases with concentration.