Radio-photoluminescence in Sm-doped BaF2-Al2O3-B2O3 glass-ceramics

In this research we have found that Sm-doped BaF2-Al2O3-B2O3 glass ceramics show radio-photoluminescence (RPL) properties associated with X-ray irradiation. Before X-ray irradiation, the photoluminescence (PL) emission is only due to the 4f-4f transitions of Sm3+ observed around 600 nm; however, after X-ray irradiation it shows additional PL emissions due to the 4f-4f transitions of Sm2+. We attributed the origin of this RPL due to the inter-valence conversion of Sm ion (Sm3+ → Sm2+). The glass ceramic sample includes BaAlBO3F2 crystallites in the glass matrix, and the RPL is only valid for Sm included in the crystalline phase since the precursor glass (without the crystalline phase) does not show RPL. The RPL response is so stable that it does not show any indication of fading even by heating at high temperatures up to 400 °C. For radiation sensing applications, we have confirmed that it shows a monotonically increasing response with X-ray dose at least over the 10-10,000 mGy; and it has been demonstrated for 2D dosimetry applications.