Capture cross sections of point defects in semiconductors

The treatment of multiphonon processes by which electronic energy is dissipated to the lattice has been hampered by an extremely rapid increase in the number of multiphonon configurations that can be formed as the number of included phonon modes is increased. Here, we employ the general theory developed in Ref. 1 for nonradiative capture of carriers by defects in semiconductors, based on density functional theory. We replace the Monte Carlo method of integrating over phonon modes with a much faster time-domain integration method that includes all phonon modes in the computational supercell. We also report results for both zeroth- and first-order contributions to carrier-capture cross sections in two cases: electron capture by a model Si dangling bond in a triply-hydrogenated vacancy in Si and hole capture by a C_N substitutional impurity in GaN.

[1] G. D. Barmparis, Y. S. Puzyrev, X.-G. Zhang, and S. T. Pantelides, Phys. Rev. B 92, 214111 (2015).