Stimulated luminescence emission from localized recombination in randomly distributed defects

Mayank Jain, Benny Guralnik, Martin Thalbitzer Andersen

    Research output: Contribution to journalJournal articleResearchpeer-review

    Abstract

    We present a new kinetic model describing localized electronic recombination through the excited state of the donor (d) to an acceptor (a) centre in luminescent materials. In contrast to the existing models based on the localized transition model (LTM) of Halperin and Braner (1960 Phys. Rev. 117 408–15) which assumes a fixed d → a tunnelling probability for the entire crystal, our model is based on nearest-neighbour recombination within randomly distributed centres. Such a random distribution can occur through the entire volume or within the defect complexes of the dosimeter, and implies that the tunnelling probability varies with the donor–acceptor (d–a) separation distance. We first develop an ‘exact kinetic model’ that incorporates this variation in tunnelling probabilities, and evolves both in spatial as well as temporal domains. We then develop a simplified one-dimensional, semi-analytical model that evolves only in the temporal domain. An excellent agreement is observed between thermally and optically stimulated luminescence (TL and OSL) results produced from the two models. In comparison to the first-order kinetic behaviour of the LTM of Halperin and Braner (1960 Phys. Rev. 117 408–15), our model results in a highly asymmetric TL peak; this peak can be understood to derive from a continuum of several first-order TL peaks. Our model also shows an extended power law behaviour for OSL (or prompt luminescence), which is expected from localized recombination mechanisms in materials with random distribution of centres.
    Original languageEnglish
    JournalJournal of Physics: Condensed Matter
    Volume24
    Issue number38
    Pages (from-to)385402
    Number of pages13
    ISSN0953-8984
    DOIs
    Publication statusPublished - 2012

    Fingerprint Dive into the research topics of 'Stimulated luminescence emission from localized recombination in randomly distributed defects'. Together they form a unique fingerprint.

    Cite this