Low-Energy Polaron Spectra in the Doped Fröhlich Model

ORAL

Abstract

We investigate the low-energy electron quasiparticle spectrum of the doped
Fröhlich solid as a model system for electron-phonon coupling in doped polar
semiconductors. Substantial improvements in the resolution of photoemission
spectroscopy have given access to the low-energy physics in these
systems, and have shown that electron-phonon interactions are at the core of a
wide range of intriguing properties, from high electron mobility to superconductivity.
In view of these advances, a sound theoretical description of energy levels and
effective masses in the doped Fröhlich solid is called for. In our study, we present
analytical results for the momentum-resolved spectral function as obtained from the
interacting electron Green’s function. We employ both the first-order
Migdal approximation and the higher-order Cumulant Expansion approach.
We find that the treatment of polaron satellites using the Cumulant Expansion achieves
much better agreement with experiment, albeit at the price of a poorer description of
quasiparticle dispersion relations.

*Work supported as part of the Computational Materials
Sciences Program funded by the U.S. Department of Energy,
Office of Science, Basic Energy Sciences, under Award No.
DE-SC0020129, and by the Robert A. Welch Foundation
under award number F-1990-20190330.

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Presenters

  • Nikolaus Kandolf

    • ODEN Institute for Computational Engineering and Sciences, University of Texas at Austin

Authors

  • Nikolaus Kandolf

    • ODEN Institute for Computational Engineering and Sciences, University of Texas at Austin

  • Carla Verdi

    • University of Vienna
    • Univ of Vienna
    • Department of Materials, University of Oxford

  • Feliciano Giustino

    • Physics, University of Texas at Austin
    • University of Texas at Austin
    • Oden Institute for Computational Engineering and Sciences, University of Texas at Austin
    • Department of Physic, The University of Texas at Austin, Austin, Texas 78712, USA, Oden Institute for Computational Engineering and Sciences
    • Oden Institute, University of Texas at Austin
    • Department of Materials, University of Oxford
    • Department of Physics, University of Texas at Austin
    • ODEN Institute for Computational Engineering and Sciences, University of Texas at Austin