Crystal Growth and Scintillation Properties of Tm, Nd Codoped LaF$_{3}$ Single Crystals

Because there is an overlap of the 5d-4f emission transition of Tm
³⁺
and absorption transition of Nd
³⁺
, an energy transfer between Nd
³⁺
and Tm
³⁺
in LaF
₃
was supposed to enhance the efficiency of the previously studied Nd:LaF
₃
scintillation material. In this study, 0.1% and 1%Tm, Nd, and Tm, Nd codoped LaF
₃
single crystals scintillators were developed using micro-pulling down method (μ-PD), and their optical properties in the vacuum ultraviolet (VUV) region were evaluated. Tm
³⁺
codopant did not show positive contribution to VUV emission, but energy transfer between Nd
³⁺
and Tm
³⁺
cannot be excluded, although the photoluminescence spectra point just to a competition for energy between the two ions. Gamma-ray response was also measured using the pulse-height distribution measurement.