Optical determination of the width of the band-tail states, and the excited state and ground state energies of the principal dosimetric trap in feldspar
Abstract
We constrain parameters that determine thermal stability of the infrared stimulated luminescence (IRSL) signal in a suite of 13 compositionally different feldspar samples by optical probing. We focus specifically on the excited and ground state of the principal trap and the width of the sub-conduction band-tail states. Excitation spectra measured at room temperature result in approximate trap depth of about 2.04 eV and the excited state energy at 1.44 ± 0.02 eV, irrespective of feldspar composition for the sample's measured here. Fitting the non-resonant rising continuum of the excitation spectra suggests that the width of the band-tail states accessible from the ground state of the trap (ΔE) ranges from 0.21 to 0.47 eV at room temperature between the different samples. Photoluminescence measurements are used to constrain the full sub-conduction band-tail width (Urbach width, Eu) using the excitation-energy-dependent emission (EDE), resulting in values ranging from 0.26 to 0.81 eV. While the depth of the principal trap and its main excited state seem to be independent of feldspar composition, the difference between ΔE and Eu seems to be related to sample K-content.
Citation
Riedesel , S , King , G E , Prasad , A K , Kumar , R , Finch , A A & Jain , M 2019 , ' Optical determination of the width of the band-tail states, and the excited state and ground state energies of the principal dosimetric trap in feldspar ' , Radiation Measurements , vol. 125 , pp. 40-51 . https://doi.org/10.1016/j.radmeas.2018.08.019
Publication
Radiation Measurements
Status
Peer reviewed
ISSN
1350-4487Type
Journal article
Rights
© 2018 Elsevier Ltd. This work has been made available online in accordance with the publisher’s policies. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at: https://doi.org/10.1016/j.radmeas.2018.08.019
Description
SR performed the measurements during her M.Sc., which was financially supported by the Deutschlandstipendium of the Bundesministerium für Bildung und Forschung – Stiftung Studium und Lehre (Ministry for Education and Research of the German government). The paper was written, during SR's PhD, which is financed by an AberDoc PhD Scholarship of Aberystwyth University. An Erasmus + student mobilitygrant enabled SR's research stay at the Center for Nuclear Technologies, Technical University of Denmark, DTU Risø Campus, Roskilde, Denmark. GEK acknowledges support from SNSF grant number PZ00P2_167960. Samples HAM-5 and JSH1-13 were taken in the framework of the QuakeRecNankai project, funded by the Belgian Science Policy Office (BELSPO BRAIN-be BR/121/A2). We thank Benny Guralnik for the provision of KTB-383-C, Renske Lambert for MBT-I-2430 and MBT-F-5704, Javier Garcia-Guinea for Cleavelandite and David Sanderson for F1.Collections
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