Abstracts 2003

Abstract of Publication No. 450

S. Heer, K. Petermann and H. U. Güdel
Upconversion excitation of Cr3+ emission in YAlO3 codoped with Cr3+ and Yb3+
J. Lumin. 102-103, 144-150 (2003)      Full Text (PDF)      DOI-Link     

Abstract: We report on upconversion (UC) luminescence in YAlO3 codoped with 0.3% Cr3+ and 6% Yb3+. At 10 K excitation around 10,400 cm–1 leads to red Cr3+ pair luminescence at 14,000 cm–1. The UC excitation spectrum of the red Cr3+ luminescence is very similar to the squared Yb3+ absorption spectrum. This demonstrates that two Yb3+ 2F7/22F5/2 excitations are involved in the UC process. From transient measurements, the UC mechanism is found to be dominated by an energy transfer step: Two excited Yb3+ ions simultaneously transfer their excitation energy to a nearby Cr3+ pair.

Last modified: 13.12.11 by Gabriela Frei