Up-converted blue emission has been generated in a 1 at.% P3+:Be2La2O5 crys
tal after orange and infra-red excitation. The responsible up-conversion me
chanisms were investigated and shown to be energy transfer and excited stat
e absorption, respectively. The dynamics of the involved excited states hav
e been studied under pulsed laser excitation. These results are compared wi
th those for Pr3+ ion in different laser crystals. (C) 2000 Elsevier Scienc
e S.A. All rights reserved.