Materials Sciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, Mail Stop 66, Berkeley, California 94720, USA.
Phys Rev Lett. 2012 Dec 14;109(24):245501. doi: 10.1103/PhysRevLett.109.245501. Epub 2012 Dec 10.
Nonradiative carrier recombination is of both applied and fundamental interest. Here a novel algorithm is introduced to calculate such a deep level nonradiative recombination rate using the ab initio density functional theory. This algorithm can calculate the electron-phonon coupling constants all at once. An approximation is presented to calculate the phonon modes for one impurity in a large supercell. The neutral Zn impurity site together with a N vacancy is considered as the carrier-capturing deep impurity level in bulk GaN. Its capture coefficient is calculated as 5.57 × 10(-10)cm(3)/s at 300 K. We found that there is no apparent onset of such a nonradiative process as a function of temperature.
非辐射载流子复合具有应用和基础研究的双重兴趣。这里引入了一种新的算法，使用从头算密度泛函理论来计算这种深能级非辐射复合率。该算法可以一次性计算电子-声子耦合常数。提出了一种在大超胞中计算单个杂质声子模式的近似方法。中性 Zn 杂质位与一个 N 空位一起被认为是体 GaN 中的载流子俘获深杂质能级。在 300 K 时，其俘获系数计算值为 5.57×10(-10)cm(3)/s。我们发现，作为温度的函数，这种非辐射过程没有明显的开始。
