Thermoluminescence of $ZrO2$ doped with $Yb2O3$ following excitation with x rays

This study examines the thermoluminescence (TL) of ytterbium oxide $(Yb2O3)$-doped zirconia $(ZrO2)$ in response to ultraviolet (UV) and synchrotron x-ray excitations. Experimental results demonstrate that, as well as a strong TL peak at $105°C$ and a weak peak at $205°C$⁠, another small peak appears at $150°C$⁠. The TL peak at $150°C$ exhibits dopant concentration quenching. The intensity of the two small peaks, particularly that at $150°C$⁠, increases rapidly with the energy of the photons. However, increasing the doping concentration of $Yb2O3$ reduces the intensity of both TL peaks at 105 and $205°C$⁠, and reduces the $ZrO2$ content in the monoclinic phase. This finding indicates that the intensities of both TL peaks at 105 and $205°C$ are associated with the $ZrO2$ content in the monoclinic phase. Additionally, the TL glow remains clearly observed from both undoped and doped samples after $48h$ of storage. Doping $ZrO2$ with $Yb2O3$ reduces the rate of fading of TL from the undoped $ZrO2$ sample. The stable TL peak of the $Yb2O3$ dopant at $150°C$ indicates its greater effectiveness than pure $ZrO2$ in dosimetry. These observations and their implications are discussed.