Carbon doped yttrium aluminum garnet (YAG:C)—A new phosphor for radiation dosimetry

Carbon doped yttrium aluminum garnet (YAG:C) samples were prepared by a simple process involving melting of polycrystalline YAG powder in graphite environment using electron gun of a vacuum deposition system meant for deposition of thin films. The samples showed excellent TL and OSL response in the dose range of 10 mGy to 100 Gy. However, the YAG treated in a similar manner but in the absence of graphite showed poor TL and OSL sensitivity for low doses. The TL emission spectrum of YAG:C showed three peaks at 378, 420 and 440 nm. This treatment has significantly improved the detection threshold down to 10 mGy, which is relevant to personal dosimetry. The results indicate that this method can efficiently generate adequate concentration of dosimetrically useful defects in YAG. The suitability of these samples for the radiation dosimetry has been ascertained. Samples stored at room temperature in the dark have been found to have negligible post irradiation fading for a period of two months.