Positron lifetimes and trapping probabilities observed separately for vacancies and dislocations in aluminium
Positron lifetimes and trapping probabilities observed separately for vacancies and dislocations in aluminium
复制标题
分别观察铝中的空位和位错的正电子寿命和俘获概率
DOI：
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发表时间：
1972
期刊：
影响因子：
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通讯作者：
J. Träff
中科院分区：
文献类型：
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作者：
R. Cotterill;K. Petersen;G. Trumpy;J. Träff
本文研究了正电子在铝中的湮没特性，包括在完全晶格中的湮没和在空位或位错处俘获后的湮没。用淬火和退火方法在单晶铝中控制空位和位错的产生。理想晶格中的湮没寿命为166+或-2 ps，而陷在空位中的正电子的湮没寿命为246+或-4 ps，陷在位错中的正电子的湮没寿命为250+或-30 ps。发现平均寿命随着位错密度的增加而增加，但通过淬火工艺获得的位错密度并没有达到饱和。空位的俘获几率为（0.23+或-0.05）× 1015 s-1，位错的俘获几率为（0.08+或-0.05）× 1015 s-1.
The annihilation characteristics of positrons in aluminium have been studied for the distinct cases of annihilation in the perfect lattice and annihilation after trapping at vacancies or dislocations. A controlled production of vacancies and dislocation in single crystal aluminium specimens was achieved with a quenching and annealing procedure. The annihilation lifetime in the perfect lattice is 166+or-2 ps, whereas it is 246+or-4 ps for positrons trapped in vacancies and 250+or-30 ps for positrons trapped in dislocations. The mean lifetime is found to increase with increasing dislocation density, but saturation is not attained with the dislocation densities obtainable by the quenching process. The trapping probabilities are (0.23+or-0.05)*1015 s-1 for vacancies and (0.08+or-0.05)*1015 s-1 for dislocations.