Print Email Facebook Twitter Experimental and numerical analysis of Tm2+ excited-states dynamics and luminescence in CaX2 (X = Cl, Br, I) Title Experimental and numerical analysis of Tm2+ excited-states dynamics and luminescence in CaX2 (X = Cl, Br, I) Author Plokker, M.P. (TU Delft RST/Luminescence Materials) van der Knijff, I.C. (TU Delft Optical Technologies) de Wit, A.V. (Student TU Delft) Voet, B. (Student TU Delft) Woudstra, T. (Student TU Delft) Khanin, V. (TU Delft RST/Luminescence Materials) Dorenbos, P. (TU Delft RST/Luminescence Materials) van der Kolk, E. (TU Delft RST/Luminescence Materials) Date 2021 Abstract The prospect of using Tm2+-doped halides for luminescence solar concentrators (LSCs) requires a thorough understanding of the temperature dependent Tm2+ excited states dynamics that determines the internal quantum efficiency (QE) and thereby the efficiency of the LSC. In this study we investigated the dynamics in CaX2:Tm2+ (X = Cl, Br, I) by temperature- and time-resolved measurements. At 20 K up to four distinct Tm2+ emissions can be observed. Most of these emissions undergo quenching via multi-phonon relaxation below 100 K. At higher temperatures, only the lowest energy 5d–4f emission and the 4f–4f emission remain. Fitting a numerical rate equation model to the data shows that the subsequent quenching of the 5d–4f emission is likely to occur initially via multi-phonon relaxation, whereas at higher temperatures additional quenching via interband crossing becomes thermally activated. At room temperature only the 4f–4f emission remains and the related QE becomes close to 30%. Possible reasons for the quantum efficiency not reaching 100% are provided. Subject CaCl:Tm CaBr:Tm CaI:Tm+Luminescence quenchingPhotoluminescenceRate equations modellingTm doped halidesTm excited states dynamics To reference this document use: http://resolver.tudelft.nl/uuid:2235501a-5ecc-4c13-a8f6-e98dfe28546d DOI https://doi.org/10.1088/1361-648X/abfa5d ISSN 0953-8984 Source Journal of Physics: Condensed Matter, 33 (25) Part of collection Institutional Repository Document type journal article Rights © 2021 M.P. Plokker, I.C. van der Knijff, A.V. de Wit, B. Voet, T. Woudstra, V. Khanin, P. Dorenbos, E. van der Kolk Files PDF Plokker_2021_J._Phys._Con ... 255701.pdf 2.69 MB Close viewer /islandora/object/uuid:2235501a-5ecc-4c13-a8f6-e98dfe28546d/datastream/OBJ/view