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Strain and stress relationships for optical phonon modes in monoclinic crystals with +¦-Ga2 O3 as an example

Korlacki, R. ; Stokey, M. ; Mock, A. ; Knight, S. LU ; Papamichail, A. ; Darakchieva, V. LU and Schubert, M. LU orcid (2020) In Physical Review B 102(18).
Abstract

Strain-stress relationships for physical properties are of interest for heteroepitaxial material systems, where strain and stress are inherent due to thermal expansion and lattice mismatch. We report linear perturbation theory strain and stress relationships for optical phonon modes in monoclinic crystals for strain and stress situations which maintain the monoclinic symmetry of the crystal. By using symmetry group analysis and phonon frequencies obtained under various deformation scenarios from density-functional perturbation theory calculations on +¦-Ga2O3, we obtain four strain and four stress potential parameters for each phonon mode. We demonstrate that these parameters are sufficient to describe the frequency shift of the modes... (More)

Strain-stress relationships for physical properties are of interest for heteroepitaxial material systems, where strain and stress are inherent due to thermal expansion and lattice mismatch. We report linear perturbation theory strain and stress relationships for optical phonon modes in monoclinic crystals for strain and stress situations which maintain the monoclinic symmetry of the crystal. By using symmetry group analysis and phonon frequencies obtained under various deformation scenarios from density-functional perturbation theory calculations on +¦-Ga2O3, we obtain four strain and four stress potential parameters for each phonon mode. We demonstrate that these parameters are sufficient to describe the frequency shift of the modes regardless of the stress or strain pattern which maintain the monoclinic symmetry of the crystal. The deformation potentials can be used together with experimentally determined phonon frequency parameters from Raman or infrared spectroscopy to evaluate the state of strain or stress of +¦-Ga2O3, for example, in epitaxial heterostructures.

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author
; ; ; ; ; and
publishing date
type
Contribution to journal
publication status
published
in
Physical Review B
volume
102
issue
18
article number
180101
publisher
American Physical Society
external identifiers
  • scopus:85097128672
ISSN
2469-9950
DOI
10.1103/PhysRevB.102.180101
language
English
LU publication?
no
additional info
Publisher Copyright: © 2020 American Physical Society.
id
7dd20e4c-1686-4094-903d-a0c25faccc24
date added to LUP
2025-11-06 16:37:41
date last changed
2025-11-11 15:22:00
@article{7dd20e4c-1686-4094-903d-a0c25faccc24,
  abstract     = {{<p>Strain-stress relationships for physical properties are of interest for heteroepitaxial material systems, where strain and stress are inherent due to thermal expansion and lattice mismatch. We report linear perturbation theory strain and stress relationships for optical phonon modes in monoclinic crystals for strain and stress situations which maintain the monoclinic symmetry of the crystal. By using symmetry group analysis and phonon frequencies obtained under various deformation scenarios from density-functional perturbation theory calculations on +¦-Ga2O3, we obtain four strain and four stress potential parameters for each phonon mode. We demonstrate that these parameters are sufficient to describe the frequency shift of the modes regardless of the stress or strain pattern which maintain the monoclinic symmetry of the crystal. The deformation potentials can be used together with experimentally determined phonon frequency parameters from Raman or infrared spectroscopy to evaluate the state of strain or stress of +¦-Ga2O3, for example, in epitaxial heterostructures.</p>}},
  author       = {{Korlacki, R. and Stokey, M. and Mock, A. and Knight, S. and Papamichail, A. and Darakchieva, V. and Schubert, M.}},
  issn         = {{2469-9950}},
  language     = {{eng}},
  month        = {{11}},
  number       = {{18}},
  publisher    = {{American Physical Society}},
  series       = {{Physical Review B}},
  title        = {{Strain and stress relationships for optical phonon modes in monoclinic crystals with +¦-Ga2 O3 as an example}},
  url          = {{http://dx.doi.org/10.1103/PhysRevB.102.180101}},
  doi          = {{10.1103/PhysRevB.102.180101}},
  volume       = {{102}},
  year         = {{2020}},
}