α-Al_2O_3:C单晶的β辐射热释光与光释光性能研究  

Thermoluminescence and optically stimulated luminescence performance of β-radiated α-Al_2O_3: C crystal

作　　者：范志鹏[1,2] 杜景红[1] 邹宇琦[2] 王静雅[2] 姜大朋[2] 徐军[2] 

机构地区：[1]昆明理工大学材料科学与工程学院,昆明650093 [2]中国科学院上海硅酸盐研究所,上海201800

出　　处：《辐射研究与辐射工艺学报》2015年第2期61-64,共4页Journal of Radiation Research and Radiation Processing

基　　金：国家自然科学基金项目(61177037)资助

摘　　要：以高纯碳粉作为碳源直接加入原料,采用导模法(EFG)生长了α-Al2O3:C单晶。研究了晶体经过低剂量β射线辐照后的热释光与光释光特性,α-Al2O3:C单晶的热释光发光曲线在350 K、540 K和689 K附近有3个热释光峰,540 K附近为主要热释光峰,689 K附近为新的热释光峰,发现晶体的陷阱能级深度发生变化并产生了新深度的陷阱能级;随着β吸收剂量的增加,发光强度也随之增强,但是3个热释光峰温位置大致保持不变。在多次连续同剂量辐照过程中,随着辐照次数的增加,主热释光峰强度增强,峰温向高温方向偏移。α-Al2O3:C单晶的光释光衰减曲线呈指数变化,其由前期快衰减部分和后期慢衰减部分组成,快衰减部分衰减速率随着吸收剂量的增加变化很小,而慢衰减部分衰减速率则有较为明显的减慢。在低剂量范围内(低于10Gy),热释光和光释光过程灵敏度不随吸收剂量而变化,剂量响应曲线呈线性的特点。α-Al2O3：C crystal was grown by edge-defined film-fed grown technique（EFG） using high-purity graphite powder as carbon source. The thermoluminescence（TL） and optically stimulated luminescence properties（OSL） of low doses of β were investigated. The crystal shows three TL peaks at near 350, 540 and 689 K after irradiation with a β-rays source： the peak at near 540 K is the main TL peak, and the peak at near 689 K is the new TL peak. The depth of trap level of crystal has changes and produce trap level of new depth; the TL intensity increased with the irradiation doses, but no change is found in the position of TL peak. As the times of irradiation increase in the process of many consecutive irradiation of the same dose, the main TL peak intensity increases and the peak temperature shift to the direction of high temperature. The OSL decay curve of α-Al2O3：C crystal consists of the early-fast component and the late-slow component. With the increasing irradiation dose, the decay rate of the early-fast component changes slightly while that of the late-slow component decreased obviously. The TL and OSL dose response of the crystal shows excellent linear characteristic in the low dose range.

关 键 词：α-Al2O3:C Β射线 热释光 光释光 

分 类 号：TL81[核科学技术—核技术及应用]