We reported the photoluminescence (PL) properties of thallium bromide- (TlBr) crystals exhibiting high performance as γ-ray detectors. The excitation intensity dependence of PL emission intensity and the location dependence of PL spectra were investigated. It was found that the TlBr crystals with higher mobility-lifetime products has higher emission intensity of PL spectrum on the high energy side. The PL of TlBr crystals are attributed to free exciton of indirect band gap and defect levels. Difference in emission intensity is obtained depending on the location of the TlBr crystals as a whole.
