Traps and recombination centers in YALO3:Ce,Co

It has recently been noted that notorious underperfomance of YAlO3:Ce scintillator (25–30 ns scintillation decay time at room temperature instead of 17 ns) is caused by uncontrolled traps that accompany Ce radiative recombination centers. A possible way to improve the material is to introduce a second intentional dopant that would assume a role of shallow trap preventing deeper traps from interfering with the scintillation process. In this communication, we present initial results of studies on YAP:Ce,Co. Experimental results include radioluminescence spectra, VUV spectroscopy and scintillation light yields. We conclude that Co-codoping of YAP:Ce fails to produce a desired effect on scintillation kinetics. Apparently Co ions do not assume a role of shallow traps but, instead, become active recombination centers that compete with Ce ions in the YAP matrix introducing other slow emissions that lower the scintillation light yield.