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Efficient calculation of carrier scattering rates from first principles.

ABSTRACT: The electronic transport behaviour of materials determines their suitability for technological applications. We develop a computationally efficient method for calculating carrier scattering rates of solid-state semiconductors and insulators from first principles inputs. The present method extends existing polar and non-polar electron-phonon coupling, ionized impurity, and piezoelectric scattering mechanisms formulated for isotropic band structures to support highly anisotropic materials. We test the formalism by calculating the electronic transport properties of 23 semiconductors, including the large 48 atom CH₃NH₃PbI₃ hybrid perovskite, and comparing the results against experimental measurements and more detailed scattering simulations. The Spearman rank coefficient of mobility against experiment (r_s = 0.93) improves significantly on results obtained using a constant relaxation time approximation (r_s = 0.52). We find our approach offers similar accuracy to state-of-the art methods at approximately 1/500th the computational cost, thus enabling its use in high-throughput computational workflows for the accurate screening of carrier mobilities, lifetimes, and thermoelectric power.

SUBMITTER: Ganose AM

PROVIDER: S-EPMC8044096 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Efficient calculation of carrier scattering rates from first principles.

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