Bandstructure, optical spectra, and mean free paths in the room-temperature structure of CH$_{3}$NH$_{3}$PbI$_{3}$ from many-body perturbation theory

ORAL

Abstract

The organometallic halide pervoskites have generated enormous interest due to the rapidly increasing efficiency of solar cells fabricated from these materials. Most research on the organometallic halide pervoskites has been experimental due to the challenges posed by these materials to theoretical study, including the size of the unit cell, the presence of many defects, the orientational disorder in of the methyammonium (MA) cation, and the heavy atoms involved with the corresponding large spin-orbit coupling (SOC). We study the room-temperature tetragonal structure of CH$_{3}$NH$_{3}$PbI$_{3}$ using density functional theory (DFT) and a many-body Green's functions approach. We use DFT to study the effect of the dependence of the bandstructure on the orientation of the MA cation, while we perform GW and GW plus Bethe-Salpeter equation (GW-BSE) calculations to study the quasiparticle bandstructure and optical spectra, respectively, paying close attention to convergence and the effect of SOC. We particularly investigate the existence of a proposed charge-transfer state in this material. We also briefly discuss the mean free paths due to electron-phonon and electron-electron scattering in the ideal structure.

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Authors

  • Derek Vigil-Fowler

    University of California at Berkeley and Lawrence Berkeley National Lab

  • Marco Bernardi

    University of California at Berkeley and Lawrence Berkeley National Lab, Department of Physics, University of California, Berkeley, and Materials Science Division, Lawrence Berkeley National Lab, Berkeley, CA 94720, USA

  • Steven G. Louie

    University of California at Berkeley, Lawrence Berkeley National Lab, University of California - Berkeley and Lawrence Berkeley National Lab, Department of Physics, University of California at Berkeley; Materials Sciences Divisions, Lawrence Berkeley National Laboratory, Univ of California - Berkeley and Lawrence Berkeley National Lab, Department of Physics, UC Berkeley and Lawrence Berkeley National Lab, University of California, Berkeley and Lawrence Berkeley National Laboratory, University of California at Berkeley and Lawrence Berkeley National Laboratory, UC Berkeley and Lawrence Berkeley National Lab, University of California at Berkeley and Lawrence Berkeley National Lab, Physics Department, UC Berkeley and Lawrence Berkeley National Lab, Department of Physics, University of California, Berkeley, and Materials Science Division, Lawrence Berkeley National Lab, Berkeley, CA 94720, USA, UC Berkeley physics/ LBNL MSD