Dissemin is shutting down on January 1st, 2025

Published in

Elsevier, Journal of Luminescence, 10(132), p. 2753-2762

DOI: 10.1016/j.jlumin.2012.05.028

Links

Tools

Export citation

Search in Google Scholar

Luminescence and energy transfer mechanisms in CaWO4 single crystals

Journal article published in 2012 by D. Spassky ORCID, V. Mikhailin, M. Nazarov, M. N. Ahmad Fauzi, A. Zhbanov
This paper is available in a repository.
This paper is available in a repository.

Full text: Download

Green circle
Preprint: archiving allowed
Red circle
Postprint: archiving forbidden
Red circle
Published version: archiving forbidden
Data provided by SHERPA/RoMEO

Abstract

The processes of the excitation energy transfer to the emission centers have been investigated for calcium tungstate crystals taking into account features of the electronic structure of valence band and conduction band. The calculations of the electronic structure of host lattice CaWO4 were performed in the framework of density functional theory. The underestimation of the bandgap value in the calculations has been corrected according to the experimental data. Luminescence of two samples grown using Czochralski (cz) and hydrothermal (ht) techniques were studied. Intrinsic emission band related to excitons, self-trapped on WO4 complexes has been observed for the both samples while the additional low-energy emission band related to the defects of crystal structure has been observed only for (ht) sample indicating the enhanced concentration of the defects in the sample. It was shown that the features of the conduction band electronic structure are reproduced in the excitation spectrum of intrinsic luminescence only for the (ht) sample while for (cz) sample the correlation is absent. The enhanced role of the competitive channels in the process of excitation energy transfer to intrinsic emission centers in (ht) sample is responsible for the observed difference.