Correlated multi-particle excitations: Green’s function formalism for trions and biexcitons

Invited

Abstract

With the experimental isolation of atomically thin one- and two-dimensional materials, it is now possible to measure a variety of charged and neutral multiparticle excitations (trions, biexcitons, etc.) in these systems, many of which display large binding energies. On the theory side, however, while quasiparticle and neutral optical excitations have been successfully treated in many materials with the first-principles GW and GW plus Bethe-Salpeter equation (GW-BSE) approaches, respectively, similar many-body and parameter-free approaches are not available to compute and understand correlated multi-particle excitations. Accordingly, past theoretical studies were often limited to treatments based on model Hamiltonians. In this talk, we present results from a new ab initio approach based on the interacting 3- and 4-particle Green’s function formalism to compute multiparticle excitations [1]. Our new diagrammatic approach that makes use of appropriate screened Coulomb interactions, combined with a high-performance computing implementation, allows us to predict without adjustable parameters that trions and biexcitons in carbon nanotubes are stable at room temperature, and also to reveal in details electronic correlation in these multiparticle excitations. We will also comment on how this formalism can be employed to investigate other high-order excited-state phenomena in the bulk and at the nanoscale.

[1] F. H. da Jornada, A. Cepellotti, and S. G. Louie, submitted.

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Presenters

  • Felipe Da Jornada

    Department of Physics, University of California, Berkeley, Department of Physics, University of California at Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory, Physics, University of California at Berkeley, Lawrence Berkeley National Laboratory, University of California at Berkeley and Lawrence Berkeley National Laboratory, Physics, University of California, Berkeley, UC Berkeley and Lawrence Berkeley National Lab, Lawrence Berkeley National Lab, Lawrence Berkeley National Lab and University of California, Berkeley

Authors

  • Felipe Da Jornada

    Department of Physics, University of California, Berkeley, Department of Physics, University of California at Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory, Physics, University of California at Berkeley, Lawrence Berkeley National Laboratory, University of California at Berkeley and Lawrence Berkeley National Laboratory, Physics, University of California, Berkeley, UC Berkeley and Lawrence Berkeley National Lab, Lawrence Berkeley National Lab, Lawrence Berkeley National Lab and University of California, Berkeley

  • Andrea Cepellotti

    University of California, Berkeley, UC Berkeley and Lawrence Berkeley National Lab, Physics and Materials Sciences, University of California at Berkeley and Lawrence Berkeley National Laboratory

  • Steven G. Louie

    Physics, UC Berkeley, University of California, Berkeley, Department of Physics, University of California, Berkeley, Physics Department, UC Berkeley and Lawrence Berkeley National Lab, Department of Physics, University of California at Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory, Physics, University of California at Berkeley, University of California at Berkeley and Lawrence Berkeley National Lab, University of California at Berkeley and Lawrence Berkeley National Laboratory, Physics, University of California, Berkeley, UC Berkeley and Lawrence Berkeley National Lab, Physics, University of California - Berkeley, Physics and Materials Sciences, University of California at Berkeley and Lawrence Berkeley National Laboratory, Lawrence Berkeley National Lab and University of California, Berkeley, University of California - Berkeley, Lawrence Berkeley National Laboratory