Abstracts 1998

Abstract of Publication No. 302

Karl W. Krämer, Hans U. Güdel and Robert N. Schwartz
NIR to VIS upconversion in LaCl3: 1% Er3+
One- and two-color excitations around 1000 and 800 nm

J. Alloys Comp. 275-277, 191-195 (1998)      Full Text (PDF)      DOI-Link     

Abstract: LaCl3: 1% Er3+ shows visible luminescence upon near infrared excitation. In a first step the 4I15/2 4I11/2 or 4I15/2 4I9/2 transitions of Er3+ are excited by infrared laser radiation around 980 or 810 nm, respectively. In a second step the 4F7/2 (490 nm), 4F3/2 (445 nm) or 2H9/2 (405 nm) levels are populated via excited state absorption from the 4I11/2 or 4I9/2 levels. The excitation wavelengths for the second step are again around 810 or 980 nm, respectively. The mechanisms of one- and two-color excitations were determined by polarized excitation spectroscopy. Efficient luminescence from those highly excited states is obtained in the blue, green and red spectral regions. The upconversion efficiency can be strongly enhanced by two-color excitation. Pure blue 4F5/2 4I15/2 and red 4F5/2 4I13/2 upconversion luminescence was detected for the first time upon NIR excitation of Er3+.

Last modified: 13.12.11 by Gabriela Frei