Judd-Ofelt analysis and crystal field calculations of Er3+ ions in new oxyfluorogermanotellurite glasses and glass-ceramics

Hayat Zanane (1, 2) , Matias Velázquez (3) , Dominique Denux (1) , Jean-René Duclère (4) , Julie Cornette (5) , Aïcha Kermaoui (2) , Hamid Kellou (2) , Michel Lahaye (6) , Sonia Buffiere (1)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
2 Laboratoire d'Electronique Quantique
3 SIMaP - Science et Ingénierie des Matériaux et Procédés
4 IRCER-AXE3 - IRCER - Axe 3 : organisation structurale multiéchelle des matériaux
5 IRCER - Institut de Recherche sur les CERamiques
6 PLACAMAT - Plateforme Aquitaine de Caractérisation des Matériaux

New 30 GeO2-30 TeO2-15 ZnO-10 Na2CO3-10 CaF2-3 La2O3-x ErF3 (x = 2, 4) glasses have been synthesized and submitted to varied heat treatments to provoke nanocrystallization in their matrix. The Er3+-doped materials containing typically 50 Å-sized nanocrystallites have been characterized by DSC, ultrapicnometry, XRD, HRTEM, EDS, SAED, optical spectroscopy and VSM techniques. A Judd-Ofelt analysis could be performed from the absorption spectra and led to refined intensity parameters. The local structural changes around Er3+ cations were mostly evidenced by important modifications of the hypersensitive optical absorption bands (4I15/2 → 2H11/2, 4I15/2 → 4G11/2) and lesser modifications of the emission cross sections and experimental lifetimes. Besides, cycling around the crystallization temperature with a VSM showed some kind of “crossover” between the Curie-Weiss behavior of the Er3+ cations dissolved in the glass and those dissolved in the nanocrystallites, with a striking change of magnetic interactions sign from anti- to ferromagnetic. The crystal field Hamiltonian could be refined in C2 symmetry, thanks to the emission and excitation spectra recorded at 80 K, and the crystal field strength calculated.

Mots clés: Glass materials; Er3+ ion spectroscopy; Rare-earth materials; Optical glass-ceramics

Domaines: Matériaux

Hayat Zanane, Matias Velázquez, Dominique Denux, Jean-René Duclère, Julie Cornette, et al.. Judd-Ofelt analysis and crystal field calculations of Er3+ ions in new oxyfluorogermanotellurite glasses and glass-ceramics. Optical Materials, 2020, 100, 109640 (8 p.). ⟨10.1016/j.optmat.2019.109640⟩. ⟨hal-02429359⟩