Europhys. Lett.
Volume 69, Number 1, January 2005
Page(s) 128 - 134
Section Interdisciplinary physics and related areas of science and technology
Published online 10 December 2004
Europhys. Lett., 69 (1), pp. 128-134 (2005)
DOI: 10.1209/epl/i2004-10314-3

The shape of the $\mth{1.55}$ $\un{\mu m}$ emission band of the $\chem{Er^{3+}}$-dopant in oxyfluoride nano-scaled glass-ceramics

V. D. Rodríguez1, V. K. Tikhomirov2, J. Méndez-Ramos1 and A. B. Seddon2

1  Departamento de Física Fundamental y Experimental, Electrónica y Sistemas Universidad de La Laguna - 38206 La Laguna, Tenerife, Spain
2  Novel Photonic Glasses Research Group, Center for Advanced Materials University of Nottingham - Nottingham NG7 2RD, UK

received 30 July 2004; accepted 2 November 2004
published online 10 December 2004

We propose a diagram showing the sequence of Stark-split energy levels for the 4I15/2 and 4I13/2 states of $\chem{Er^{3+}}$ doped into oxyfluoride, nano-scaled glass-ceramics based on low- and room temperature measurements of respective emission and absorption bands. The room temperature broadest and flattest 1.55 $\un{\mu m}$ telecommunications emission band ${}^4I_{13/2}\rightarrow {}^4I_{15/2}$ of $\chem{Er^{3+}}$ to date reported earlier for such glass-ceramics is interpreted using this framework. By investigating the low-temperature behaviour, we show that the shape of the 1.55 $\un{\mu m}$ band at room temperature is mostly due to thermal population of higher Stark sublevels in the excited 4I13/2 state. Two sites for $\chem{Er^{3+}}$ are proposed which relate, respectively, to the glassy and nano-crystalline phases of the glass-ceramics and their relative contributions to the emission spectrum are identified. The $\chem{Er^{3+}}$-site in the nano-crystalline phase is shown to be cubic with nearby charge compensation by one interstitial $\chem{F^-}$, without appreciable clustering of $\chem{Er^{3+}}$ ions.

81.05.Pj - Glass-based composites, vitroceramics.
61.46.+w - Nanoscale materials: clusters, nanoparticles, nanotubes, and nanocrystals.

© EDP Sciences 2005