On the linewidth of luminescence emission bands in alkali feldspars
article
Luminescence emission from naturally occurring feldspars has been extensively studied and reported for more than 30 years, not least because of its use in optically based radiation dosimetry. However, knowledge of the actual defects participating in the luminescence remains only partial, as are the recombination pathways that lead to the emissions. Together with new spectra in the 3 eV–6 eV energy range, we show that, when looked at collectively, the combined data for alkali feldspars display distinct trends in the emission linewidths with respect to their peak energies that enable grouping into distinct categories, with full widths at half maxima (FWHM) ranging from <0.02 eV to 1 eV. These groups cover internal transitions of simple defects, free-to-bound transitions, and recombination at sites where there are major lattice distortions. The latter group also includes the potential identification of the Self-Trapped Exciton in both KAlSi3O8 and NaAlSi3O8, appearing at 5.35 eV at 10 K with a bandwidth of 1.03 eV in each. Finally, the relevance of the combined observations to radiation measurements is briefly considered.
TNO Identifier
977092
ISSN
13504487
Source
Radiation Measurements, 158, pp. 1-8.
Publisher
Elsevier Ltd
Article nr.
106848
Pages
1-8
Files
To receive the publication files, please send an e-mail request to TNO Repository.