Structure and luminescence of BaFBr:Eu~(2+) and BaFBr:Eu~(2+), Tb~(3+) phosphors and thin films

摘要

The inclusion of Tb~(3+) ions doped into the storage phosphor BaFBr:Eu~(2+) results in increased purity of the host material as well as an improvement in the linearity of the photostimulated luminescence (PSL) intensity versus the x-ray irradiation dose. Films produced by pulsed laser deposition (PLD) also show similar results, indicating that PLD is a powerful technique for producing high quality, high purity thin films. As a result, the PSL dose response is more linear in the thin films than in the powder samples. The emission intensity of Eu~(2+) in the phosphors increases with the increasing time of x-ray irradiation while the emission intensity of Tb~(3+) remains almost constant. This result may be explained by considering the reduction of impurity Eu~(3+) ions following trapping of the photoexcited electrons. The results demonstrate that these materials are not only potentially useful for medical imaging but also show promise for use in radiation dosimetry.