ND3-SITES IN BI12SIO20-ND-V CODOPED CRYSTALS( ACTIVE)

Site-selective laser spectroscopy of Nd3+ in pure and vanadium doped B i12SiO20 (BSO) Single crystals has been carried out in order to invest igate the ion crystal-field sites. Three different Nd3+ sites which de pend on vanadium concentration have been found and optically isolated. The energy level scheme of the F-4(3/2), I-4(11/2) and I-4(9/2) multi plets for the three sites, together with the temperature dependence of the F-4(3/2) lifetime and the thermal quenching of the F-4(3/2) --> I -4(9/2) luminescence are presented. A discussion on the nature of Nd3 active sites in BSO is also given.