---
_id: '30288'
abstract:
- lang: eng
  text: Lithium niobate (LiNbO3), a material frequently used in optical applications,
    hosts different kinds of polarons that significantly affect many of its physical
    properties. In this study, a variety of electron polarons, namely free, bound,
    and bipolarons, are analyzed using first-principles calculations. We perform a
    full structural optimization based on density-functional theory for selected intrinsic
    defects with special attention to the role of symmetry-breaking distortions that
    lower the total energy. The cations hosting the various polarons relax to a different
    degree, with a larger relaxation corresponding to a larger gap between the defect
    level and the conduction-band edge. The projected density of states reveals that
    the polaron states are formerly empty Nb 4d states lowered into the band gap.
    Optical absorption spectra are derived within the independent-particle approximation,
    corrected by the GW approximation that yields a wider band gap and by including
    excitonic effects within the Bethe-Salpeter equation. Comparing the calculated
    spectra with the density of states, we find that the defect peak observed in the
    optical absorption stems from transitions between the defect level and a continuum
    of empty Nb 4d states. Signatures of polarons are further analyzed in the reflectivity
    and other experimentally measurable optical coefficients.
author:
- first_name: Falko
  full_name: Schmidt, Falko
  id: '35251'
  last_name: Schmidt
  orcid: 0000-0002-5071-5528
- first_name: Agnieszka L.
  full_name: Kozub, Agnieszka L.
  id: '77566'
  last_name: Kozub
  orcid: https://orcid.org/0000-0001-6584-0201
- first_name: Uwe
  full_name: Gerstmann, Uwe
  id: '171'
  last_name: Gerstmann
  orcid: 0000-0002-4476-223X
- first_name: Wolf Gero
  full_name: Schmidt, Wolf Gero
  id: '468'
  last_name: Schmidt
  orcid: 0000-0002-2717-5076
- first_name: Arno
  full_name: Schindlmayr, Arno
  id: '458'
  last_name: Schindlmayr
  orcid: 0000-0002-4855-071X
citation:
  ama: 'Schmidt F, Kozub AL, Gerstmann U, Schmidt WG, Schindlmayr A. Electron polarons
    in lithium niobate: Charge localization, lattice deformation, and optical response.
    In: Corradi G, Kovács L, eds. <i>New Trends in Lithium Niobate: From Bulk to Nanocrystals</i>.
    MDPI; 2022:231-248. doi:<a href="https://doi.org/10.3390/books978-3-0365-3339-1">10.3390/books978-3-0365-3339-1</a>'
  apa: 'Schmidt, F., Kozub, A. L., Gerstmann, U., Schmidt, W. G., &#38; Schindlmayr,
    A. (2022). Electron polarons in lithium niobate: Charge localization, lattice
    deformation, and optical response. In G. Corradi &#38; L. Kovács (Eds.), <i>New
    Trends in Lithium Niobate: From Bulk to Nanocrystals</i> (pp. 231–248). MDPI.
    <a href="https://doi.org/10.3390/books978-3-0365-3339-1">https://doi.org/10.3390/books978-3-0365-3339-1</a>'
  bibtex: '@inbook{Schmidt_Kozub_Gerstmann_Schmidt_Schindlmayr_2022, place={Basel},
    title={Electron polarons in lithium niobate: Charge localization, lattice deformation,
    and optical response}, DOI={<a href="https://doi.org/10.3390/books978-3-0365-3339-1">10.3390/books978-3-0365-3339-1</a>},
    booktitle={New Trends in Lithium Niobate: From Bulk to Nanocrystals}, publisher={MDPI},
    author={Schmidt, Falko and Kozub, Agnieszka L. and Gerstmann, Uwe and Schmidt,
    Wolf Gero and Schindlmayr, Arno}, editor={Corradi, Gábor and Kovács, László},
    year={2022}, pages={231–248} }'
  chicago: 'Schmidt, Falko, Agnieszka L. Kozub, Uwe Gerstmann, Wolf Gero Schmidt,
    and Arno Schindlmayr. “Electron Polarons in Lithium Niobate: Charge Localization,
    Lattice Deformation, and Optical Response.” In <i>New Trends in Lithium Niobate:
    From Bulk to Nanocrystals</i>, edited by Gábor Corradi and László Kovács, 231–48.
    Basel: MDPI, 2022. <a href="https://doi.org/10.3390/books978-3-0365-3339-1">https://doi.org/10.3390/books978-3-0365-3339-1</a>.'
  ieee: 'F. Schmidt, A. L. Kozub, U. Gerstmann, W. G. Schmidt, and A. Schindlmayr,
    “Electron polarons in lithium niobate: Charge localization, lattice deformation,
    and optical response,” in <i>New Trends in Lithium Niobate: From Bulk to Nanocrystals</i>,
    G. Corradi and L. Kovács, Eds. Basel: MDPI, 2022, pp. 231–248.'
  mla: 'Schmidt, Falko, et al. “Electron Polarons in Lithium Niobate: Charge Localization,
    Lattice Deformation, and Optical Response.” <i>New Trends in Lithium Niobate:
    From Bulk to Nanocrystals</i>, edited by Gábor Corradi and László Kovács, MDPI,
    2022, pp. 231–48, doi:<a href="https://doi.org/10.3390/books978-3-0365-3339-1">10.3390/books978-3-0365-3339-1</a>.'
  short: 'F. Schmidt, A.L. Kozub, U. Gerstmann, W.G. Schmidt, A. Schindlmayr, in:
    G. Corradi, L. Kovács (Eds.), New Trends in Lithium Niobate: From Bulk to Nanocrystals,
    MDPI, Basel, 2022, pp. 231–248.'
date_created: 2022-03-13T15:28:47Z
date_updated: 2025-12-05T14:00:04Z
ddc:
- '530'
department:
- _id: '296'
- _id: '230'
- _id: '429'
- _id: '295'
- _id: '15'
- _id: '170'
- _id: '35'
- _id: '790'
doi: 10.3390/books978-3-0365-3339-1
editor:
- first_name: Gábor
  full_name: Corradi, Gábor
  last_name: Corradi
- first_name: László
  full_name: Kovács, László
  last_name: Kovács
language:
- iso: eng
page: 231-248
place: Basel
project:
- _id: '53'
  name: 'TRR 142: TRR 142'
- _id: '55'
  name: 'TRR 142 - B: TRR 142 - Project Area B'
- _id: '69'
  name: 'TRR 142 - B4: TRR 142 - Subproject B4'
- _id: '54'
  name: 'TRR 142 - A: TRR 142 - Project Area A'
- _id: '166'
  name: 'TRR 142 - A11: TRR 142 - Subproject A11'
- _id: '168'
  name: 'TRR 142 - B07: TRR 142 - Subproject B07'
- _id: '52'
  name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing'
- _id: '53'
  name: 'TRR 142: Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten
    zu funktionellen Strukturen'
publication: 'New Trends in Lithium Niobate: From Bulk to Nanocrystals'
publication_identifier:
  eisbn:
  - 978-3-0365-3339-1
  isbn:
  - 978-3-0365-3340-7
publication_status: published
publisher: MDPI
quality_controlled: '1'
status: public
title: 'Electron polarons in lithium niobate: Charge localization, lattice deformation,
  and optical response'
type: book_chapter
user_id: '16199'
year: '2022'
...