Positron affinity in semiconductors: Theoretical and experimental studies
Positron affinity in semiconductors: Theoretical and experimental studies
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DOI：
10.1103/physrevb.59.1948
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发表时间：
1999-01
影响因子：
3.7
通讯作者：
J. Kuriplach;M. Šob;G. Brauer;W. Anwand;E.-M. Nicht;P. Coleman;N. Wagner
中科院分区：
文献类型：
--
作者：
J. Kuriplach;M. Šob;G. Brauer;W. Anwand;E.-M. Nicht;P. Coleman;N. Wagner
正电子亲合势是材料的基本体特性，它对理解正电子在界面和沉淀物处的俘获具有重要意义。基于局域密度近似和正电子广义梯度近似下电子-正电子关联的各种方法，对3C、4 H和6 H多型体SiC的${A}+$进行了理论计算，并与通过功函数测量得到的实验值进行了比较。本文讨论了${A}_{+}$的理论值和实验值之间的不一致，这是由于精确测量正电子功函数的困难以及目前研究半导体中电子-正电子关联的方法可能存在的不足。
Knowledge of the positron affinity ${A}_{+},$ a basic bulk characteristic of materials, is important to the understanding of positron trapping at interfaces and at precipitates. Theoretical calculations of ${A}_{+}$ for 3C, 4H, and 6H polytypes of SiC, based on various approaches to electron-positron correlations within the local-density approximation and the generalized gradient approximation for positrons, are compared with experimental values obtained via work-function measurements. The disagreement between theoretical and experimental values of ${A}_{+}$ is discussed in terms of difficulties in the precise measurement of the positron work function and the possible inadequacy of contemporary approaches to electron-positron correlation in semiconductors.