Loading…

Lanthanum-stabilized europium-doped cubic barium chloride: An efficient x-ray phosphor

We report the photoluminescence and x-ray luminescence of lanthanum-stabilized cubic barium chloride with europium ( Eu 2 + ) doping, of general composition Ba 1 − x − y Eu y La x Cl 2 + x . X-ray diffraction patterns confirm that the material adopts a cubic fluorite structure for x = 0.125 and 0 &l...

Full description

Saved in:
Bibliographic Details
Published in:Journal of applied physics 2010-04, Vol.107 (8), p.083516-083516-7
Main Authors: Edgar, A., Zimmermann, J., von Seggern, H., Varoy, C. R.
Format: Article
Language:English
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We report the photoluminescence and x-ray luminescence of lanthanum-stabilized cubic barium chloride with europium ( Eu 2 + ) doping, of general composition Ba 1 − x − y Eu y La x Cl 2 + x . X-ray diffraction patterns confirm that the material adopts a cubic fluorite structure for x = 0.125 and 0 < y < 0.1 . The photoluminescence shows an intense band comprising two components with maxima at 420 and 394 nm. The 394 nm band is assigned to Eu 2 + substituting for Ba 2 + giving a site of cubic symmetry, based on the excitation spectra which show a T 2 g band and E g band similar to those in cubic SrCl 2 : Eu . The 420 nm band has a very different lifetime and excitation spectrum and is assigned to Eu 2 + ions which have an associated chlorine interstitial ion. The two bands are also found in the x-ray luminescence spectra. For both bands, and an additional minor emission at 520 nm found only at low temperatures and for high Eu concentrations, there is a common excitation in the UV from 150 to 200 nm which we attribute to excitons associated with the high concentration of chlorine interstitials. ESR measurements support a two-site model for the interpretation of the optical spectra. A measurement of the x-ray luminescence intensity compared to a standard commercial Gd 2 O 2 S : Tb phosphor sheet shows approximately equal brightness.
ISSN:0021-8979
1089-7550
DOI:10.1063/1.3369162