Comparative study of ab initio nonradiative recombination rate calculations under different formalisms

Nonradiative carrier recombination is of both great applied and fundamental importance, but the correct ab initio approaches to calculate it remain to be inconclusive. Here we used five different approximations to calculate the nonradiative carrier recombinations of two complex defect structures GaP : Zn-Ga-O-P and GaN : Zn-Ga-V-N, and compared the results with experiments. In order to apply different multiphonon assisted electron transition formalisms, we have calculated the electron-phonon coupling constants by ab initio density functional theory for all phonon modes. Compared with different methods, the capture coefficients calculated by the static coupling theory are 4.30 x 10(-8) and 1.46 x 10(-7) cm(3)/s for GaP : ZnGa-OP and GaN : ZnGa-VN, which are in good agreement with the experiment results, (4(-1)(+2)) x 10(-8) and 3.0 x 10(-7) cm(3)/s, respectively. We also provided arguments for why the static coupling theory should be used to calculate the nonradiative decays of semiconductors.