Photoluminescence, optical absorption and XRD studies on X-ray irradiated terbium doped KBr crystals

This paper reports the optical absorption, photoluminescence (PL), XRD, SEM studies made on KBr:Tb3+ crystals. The integrated light intensity is enhanced by about two orders of magnitude as compared to the undoped samples in spite of some OH– present in the samples. PL of these crystals exhibits characteristic Tb3+ emissions due to transitions from the 5D3 to 5D4 levels to various levels of the 7F septet on F-bleaching X-ray irradiated crystals Z3 centers are observed. The bands observed in the emission spectra of Tb3+ doped KBr are found to be shifted to higher wavelength. The stokes-shift of KBr:Tb3+ is determined and it is found to have a large value. The XRD studies have been made to determine the crystalline structure of KBr and KBr:Tb3+ and also the Miller indices. The SEM studies made reveal the presence of microcrystalline structure.