VUV spectroscopy of Tm3+ and Mn2+ doped LiSrAlF6

LiSrAlF6 (LiSA-F) crystals doped with either Tm3+ or Mn2+ were obtained by solid-state reaction and investigated spectroscopically using synchrotron radiation in the vacuum-ultra-violet and ultra-violet spectral regions. In the Tm3+ doped LiSAF crystals, the slow spin-forbidden 5d-4f emission peaking at 166 nm with a lifetime of at least I lis was observed. The respective excitation spectrum consists of several bands in the range of 160-110 nm arising due to the 4f-5d absorption. The f-f emissions of Tm3+ are well excited in the range of 135-110 nm, but not under excitation into the lower lying d-bands. The excitation mechanisms of different emissions will be discussed including the F- to Tm3+ charge transfer excitation peaking at 127 nm in LiSAR The characteristic broad T-4(1) --> (6)A(1) emission band of Mn2+ peaking at 508 (504) nm was observed in LiSAF:Mn2+ crystal at 10 (300) K. Three intense excitation bands, tentatively ascribed to the 3d-4s transitions of Mn2+, were revealed in the range of 170-110 nm. (C) 2003 Elsevier B.V. All rights reserved.