Anomalous Auger Recombination in PbSe.
Anomalous Auger Recombination in PbSe.
复制标题
PbSe 中的反常俄歇复合。
DOI：
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发表时间：
2020
影响因子：
8.6
通讯作者：
C. G. Van de Walle
中科院分区：
文献类型：
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作者：
Xie Zhang;Jimmy‐Xuan Shen;C. G. Van de Walle
使用第一性原理的方法，我们发现，俄歇复合在PbSe是异常的三个不同的方式。首先，直接俄歇系数比具有类似带隙的其他半导体低4个数量级，这一结果可以归因于缺乏重空穴带的参与。第二，声子辅助的间接俄歇复合占主导地位，相反的共同信念，直接俄歇是占主导地位的窄隙半导体。第三，一个意想不到的弱温度依赖性的俄歇系数的观察，我们现在可以归因于俄歇过程的间接性质。对这种行为的广泛接受的解释是，带隙的不寻常的温度依赖性只是一种次要效应。我们的研究结果阐明了IV-VI族半导体中异常俄歇复合的机制，这对理解和工程载流子输运至关重要。
Using first-principles approaches we find that the Auger recombination in PbSe is anomalous in three distinct ways. First, the direct Auger coefficient is 4 orders of magnitude lower than that of other semiconductors with similar band gaps, a result that can be attributed to the lack of involvement of a heavy-hole band. Second, phonon-assisted indirect Auger recombination prevails, contrary to the common belief that direct Auger is dominant in narrow-gap semiconductors. Third, an unexpectedly weak temperature dependence of the Auger coefficient is observed, which we can now attribute to the indirect nature of the Auger process. The widely accepted explanation of this behavior in terms of an unusual temperature dependence of the band gap is only a secondary effect. Our results elucidate the mechanisms underlying the anomalous Auger recombination in IV-VI semiconductors in general, which is critical for understanding and engineering carrier transport.