Near-infrared scintillation properties of Er3+-activated potassium lanthanum gallate glasses

Near-infrared luminescent materials used as scintillators have attracted research attention for applications such as dose evaluation in a high radiation dose area. Herein, we focused on the Er 3+ -activated potassium lanthanum gallate glasses and evaluated their scintillation properties for the development of near-infrared scintillators. A Er 3+ ion was employed because of an intense near-infrared emission owing to an electronic transition between 4f levels in the Er 3+ ion. In the photoluminescence and radioluminescence spectra under X-ray, the emission component derived from the transition in the Er 3+ ion was clearly observed in the 400–1700 nm wavelength range. In addition, the decay time constants agreed well with the typical values due to the transition in the Er 3+ ion when irradiated by visible light or X-ray. Furthermore, their scintillation performance was tested with a InGaAs PIN photodiode, and the detectable dose rate limit when used with the Er 3+ -activated potassium lanthanum gallate glasses and the photodiode was 5 mGy/h. The limit was comparable to the that of inorganic single crystal scintillators such as Er 3+ -doped Bi 4 Ge 3 O 12 , indicating that Er 3+ -activated gallate glasses are promising for near-infrared scintillators.