Photoluminescence of Trivalent Dysprosium Ions in Silver-Doped Aluminophosphate Glasses
J.A. Jiménez, S. Lysenko, H. Liu
Univeristy of Puerto Rico, US
Keywords: dysprosium, energy transfer, silver, nanoparticles
Abstract:With the object of furthering the understanding of metal-rare earth interactions in a dielectric host, we have studied the spectroscopic properties of Dy3+ ions in a melt-quenched silver-doped aluminophosphate glass system, owing to the significance of dysprosium ions for optical applications. Different oxidation and aggregation states of silver are obtained by variation of silver concentration and by reduction of silver ions by tin during heat treatment, which ultimately results in Ag nanoparticles (NPs) being embedded within the amorphous host. The interactions between Dy3+ ions and several silver species including dimers and Ag NPs are investigated. Both enhancement and quenching functions of silver are observed. In particular, an enhanced UV-excited Dy3+ luminescence results from increasing concentrations of silver and tin owing to energy transfer from single Ag+ ions, Ag+-Ag+ and Ag+-Ag0 pairs, and twofold-coordinated Sn centers. Silver NP-Dy3+ interactions and likely mechanisms leading to a weakened PL are discussed.