---
_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. New Trends in Lithium Niobate: From Bulk to Nanocrystals.
MDPI; 2022:231-248. doi:10.3390/books978-3-0365-3339-1'
apa: 'Schmidt, F., Kozub, A. L., Gerstmann, U., Schmidt, W. G., & Schindlmayr,
A. (2022). Electron polarons in lithium niobate: Charge localization, lattice
deformation, and optical response. In G. Corradi & L. Kovács (Eds.), New
Trends in Lithium Niobate: From Bulk to Nanocrystals (pp. 231–248). MDPI.
https://doi.org/10.3390/books978-3-0365-3339-1'
bibtex: '@inbook{Schmidt_Kozub_Gerstmann_Schmidt_Schindlmayr_2022, place={Basel},
title={Electron polarons in lithium niobate: Charge localization, lattice deformation,
and optical response}, DOI={10.3390/books978-3-0365-3339-1},
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 New Trends in Lithium Niobate:
From Bulk to Nanocrystals, edited by Gábor Corradi and László Kovács, 231–48.
Basel: MDPI, 2022. https://doi.org/10.3390/books978-3-0365-3339-1.'
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 New Trends in Lithium Niobate: From Bulk to Nanocrystals,
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.” New Trends in Lithium Niobate:
From Bulk to Nanocrystals, edited by Gábor Corradi and László Kovács, MDPI,
2022, pp. 231–48, doi:10.3390/books978-3-0365-3339-1.'
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: 2023-04-20T15:58:51Z
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'
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'
...