Abstract Positron annihilation lifetime and Doppler-broadened gamma-ray spectra have been analyzed for slow-cooled and thermally quenched polycrystalline samples of calcium-copper-titanate. Two positron lifetimes revealing the characteristic defects in the respective samples were carefully analyzed to compare and contrast the significance of their origin and implication. A third component arising from positronium formation at the powdered particle surfaces has been considered in the analysis although its significance is lost in its very small intensity (∼ 1.1–1.2%). In the quenched sample, the defect-specific long positron lifetime (τ2) is found to larger and the mean lifetime smaller while its intensity I2 is found drastically smaller and the concentration of defects less by an order of magnitude as compared to the slow-cooled sample. The observed changes in electrical parameters of slow-cooled and quenched samples were found to have correlations with the positron annihilation lifetime and Doppler-broadened lineshape parameters.

中文翻译：

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正电子湮没光谱对钛酸钙铜缓冷淬火样品的缺陷表征

摘要 对缓慢冷却和热淬火的钛酸钙铜多晶样品的正电子湮没寿命和多普勒展宽的伽马射线光谱进行了分析。仔细分析了揭示各自样品中特征缺陷的两个正电子寿命，以比较和对比它们的起源和含义的重要性。在分析中已经考虑了由粉末颗粒表面正电子形成产生的第三种成分，尽管它的重要性在其非常小的强度（~1.1-1.2%）中消失了。在淬火样品中，发现缺陷特定的长正电子寿命 (τ2) 更大，平均寿命更小，而其强度 I2 显着更小，缺陷浓度与慢冷相比减少了一个数量级样本。