The roles of thermalized and hot carrier diffusion in determining light yield and proportionality of scintillators

Numerical modeling and comparison to experiment in the materials for which suitable parameters have been measured confirm that three of the most important material parameters for predicting proportionality and the related host‐dependent light yield (LY) of scintillators are (i) the carrier diffusion coefficients (including hole self‐trapping if present, and hot‐electron diffusion if unthermalized), (ii) the kinetic order and associated rate constant of nonlinear quenching, and (iii) deep‐trapping probability. Thermalized carrier diffusion appears sufficient to describe the main trends in oxides and semiconductors. For heavier halide hosts, it appears necessary to take account of hot‐electron diffusion to explain several important host‐dependent trends.

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