Energy Transfer Studies in Tb3+-Yb3+ Co-Doped Phosphate Glasses

Hadil Benrejeb; Kevin Soler-Carracedo; Antonio Diego Lozano-Gorrín; Sana Hraiech; Inocencio Rafael Martin

doi:10.3390/ma14226782

Energy Transfer Studies in Tb³⁺-Yb³⁺ Co-Doped Phosphate Glasses

Materials (Basel). 2021 Nov 10;14(22):6782. doi: 10.3390/ma14226782.

Authors

Hadil Benrejeb^{1

2}, Kevin Soler-Carracedo³, Antonio Diego Lozano-Gorrín^{4

5}, Sana Hraiech², Inocencio Rafael Martin^{3

5}

Affiliations

¹ Chemistry Department, Faculty of Sciences of Bizerte, Carthage University, Tunis 7021, Tunisia.
² Physical Chemistry Laboratory of Mineral Materials and Their Applications, National Center of Research in Materials Science, B.P. 73, Tunis 8027, Tunisia.
³ Physics Department, University of La Laguna, E-38200 San Cristóbal de La Laguna, Santa Cruz de Tenerife, Spain.
⁴ Chemistry Department, University of La Laguna, E-38200 San Cristóbal de La Laguna, Santa Cruz de Tenerife, Spain.
⁵ Institute of Materials and Nanotechnology (IMN), University of La Laguna, E-38200 San Cristóbal de La Laguna, Santa Cruz de Tenerife, Spain.

Abstract

Detailed optical properties of Tb³⁺-Yb³⁺ co-doped phosphate glasses were performed based on their emission spectra and decay measurements. Under blue excitation of Tb³⁺ at 488 nm, the intensity of Yb³⁺ emissions gradually enhanced upon increasing the Yb³⁺ content until 1 mol% indicated an energy transfer from Tb³⁺ to Yb³⁺. Otherwise, under near infrared excitation of Yb³⁺ at 980 nm, these glasses exhibit intense green luminescence, which led to cooperative sensitization of the ⁵D₄ level of Tb³⁺ ions. A cooperative energy transfer mechanism was proposed on the basis of the study on the influence of Yb³⁺ concentration on up-conversion emission intensity, as well as the dependence of this up-conversion intensity on near infrared excitation power. Moreover, the temporal evolution of the up-conversion emissions have been studied, which was in positive agreement with a theoretical model of cooperative up-conversion luminescence that showed a temporal emission curve with rise and decay times of the involved levels.

Keywords: decay curves; down-conversion; optical properties; rare earth; up-conversion.