Efficient 4f(3)(F-4(3/2))-> 4f(2)5d excited-state absorption in Nd3+ dopedfluoride crystals

Excited state absorption (ESA) from the F-4(3/2) metastable level of Nd3+ t o the 4f(2)5d excited configuration has been investigated in YLiF4, LiLuF4 and BaY2F8 fluoride crystals doped with Nd3+ ions. Efficient ESA cross-sect ions are obtained around 213 nm and suggest that an up-conversion pumping s cheme could be used to reach 4f(2)5d for UV tunable source. ESA from the D- 4(3/2) level to the 4f(2)5d configuration completes the study. A simple int erpretation of the results on observed interconfigurational transitions is given using electric dipole selection rules. (C) 2001 Elsevier Science B.V. All rights reserved.