Scintillation properties of Nd³⁺-doped Lu₂O ₃ ceramics in the visible and infrared regions

Nd³⁺ -doped Lu₂O₃ (Nd: Lu ₂O₃) is a candidate for an infrared scintillator because (i) Lu₂O₃ has a high density of 9.5g/cm³ and a high atomic number of 67 and (ii) Nd³⁺-doped materials emit in the infrared range and the emission lines from Nd³⁺ can be used in medical applications since human body has a transparency window between 600 and 1,100 nm. However, it is extremely difficult to fabricate Lu₂O ₃ single crystals using conventional crystal growth methods because of the high melting point (2,510 °C). Using solid-state reactions, it is much easier to fabricate Lu₂O₃ into a ceramic structure. Therefore, Nd: Lu₂O₃ transparent ceramics were fabricated using a spark plasma sintering method. This technique is comparatively simple and consumes less time than other methods such as vacuum hot pressing. The scintillation properties and transmittance spectra of the as-produced ceramics were studied in both the visible and infrared regions. Radioluminescence spectra were measured in the range 800-1,200 nm. Nd³⁺ emission lines were observed in the transparency window of human body. Thus, these ceramic materials could be a candidate for medical imaging applications.