Polarized spectral properties of Er3+ ions in NaGd(WO4)2 crystal.

Authors :: Huang, J. H.
Gong, X. H.
Chen, Y. J.
Lin, Y. F.
Liao, J. S.
Chen, X. Y.
Luo, Z. D.
Huang, Y. D.
Source :: Applied Physics B: Lasers & Optics; Sep2007, Vol. 89 Issue 1, p73-80, 8p, 4 Charts, 8 Graphs
Publication Year :: 2007
Abstract: Polarized spectral properties of Er<superscript>3+</superscript>:NaGd(WO<subscript>4</subscript>)<subscript>2</subscript> single crystal are reported. The crystal was grown by the Czochralski method. The Judd–Ofelt theory was applied to analyze the polarized absorption spectra and then calculate the spontaneous emission probabilities, radiative lifetimes, and branching ratios. Fluorescence decay curves of the <superscript>4</superscript> I <subscript>13/2</subscript>, <superscript>4</superscript> I <subscript>11/2</subscript>, and <superscript>4</superscript> S <subscript>3/2</subscript> multiplets for the Er<superscript>3+</superscript> ions were measured. Stimulated emission cross-sections of the <superscript>4</superscript> I <subscript>13/2</subscript>→<superscript>4</superscript> I <subscript>15/2</subscript> transition obtained by the Fuchtbauer–Ladenberg formula and the reciprocity method were compared. Multi-phonon relaxation rates of the crystal were estimated. Green up-conversion fluorescence around 531 and 552 nm was observed, and the possible up-conversion mechanisms were proposed. [ABSTRACT FROM AUTHOR]