RETRACTED: Effect of F− ions on spectroscopic properties of Yb3+-doped zinc–tellurite glasses Original Research Article

This article has been retracted at the request of the Editors, after a reader brought the following to their attention. Reason: The article substantially reproduces parts of articles published by the same authors in the Journal of Luminescence (“Effect of F− ions on physical and spectroscopic properties of Yb3+-doped TeO2 glasses”, Volume 113, Issues 1–2, Pages 27–32) and the Journal of Alloys and Compounds (“Fluorescence lifetime increase by introduction of F− ions in ytterbium-doped TeO2-based glasses”, Volume 393, Issues 1–2, Pages 279–282). There was also a failure to cite either of these articles. These other articles have also been retracted.