Infrared and visible scintillation of Ho${}^{3+}$-doped YAG and YLF crystals

Abstract

In our effort to develop a new kind of detector for low-energy, low-rate energy deposition events we have investigated the cathodo- and radioluminescence of Ho:YAG and Ho:YLF single crystals in an extended wavelength range from $200$nm to $2200$nm. The emission spectra of both crystals show a much more intense emission in the infrared range than in the visible one. We estimate an infrared light yield of $40$photons/keV when exciting the crystals with X-rays of energy $\approx 30$keV. The main reason of this high value is due to the Ho${}^{3+}$ ions energy levels scheme that allows efficient cross relaxation processes to occur even at low dopant concentration.

15 pages, 5 figures, to be submitted to Journal of Luminescence,