Research output: Contribution to journal › Article › peer-review
Phonons in short-period gan/aln superlattices : Group-theoretical analysis, ab initio calculations, and raman spectra. / Davydov, Valery; Roginskii, Evgenii; Kitaev, Yuri; Smirnov, Alexander; Eliseyev, Ilya; Nechaev, Dmitrii; Jmerik, Valentin; Smirnov, Mikhail.
In: Nanomaterials, Vol. 11, No. 2, 286, 02.2021, p. 1-21.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Phonons in short-period gan/aln superlattices
T2 - Group-theoretical analysis, ab initio calculations, and raman spectra
AU - Davydov, Valery
AU - Roginskii, Evgenii
AU - Kitaev, Yuri
AU - Smirnov, Alexander
AU - Eliseyev, Ilya
AU - Nechaev, Dmitrii
AU - Jmerik, Valentin
AU - Smirnov, Mikhail
N1 - Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.
PY - 2021/2
Y1 - 2021/2
N2 - We report the results of experimental and theoretical studies of phonon modes in GaN/AlN superlattices (SLs) with a period of several atomic layers, grown by submonolayer digital plasma-assisted molecular-beam epitaxy, which have a great potential for use in quantum and stress engi-neering. Using detailed group-theoretical analysis, the genesis of the SL vibrational modes from the modes of bulk AlN and GaN crystals is established. Ab initio calculations in the framework of the density functional theory, aimed at studying the phonon states, are performed for SLs with both equal and unequal layer thicknesses. The frequencies of the vibrational modes are calculated, and atomic displacement patterns are obtained. Raman spectra are calculated and compared with the experimental ones. The results of the ab initio calculations are in good agreement with the experimental Raman spectra and the results of the group-theoretical analysis. As a result of comprehensive studies, the correlations between the parameters of acoustic and optical phonons and the structure of SLs are obtained. This opens up new possibilities for the analysis of the structural characteristics of short-period GaN/AlN SLs using Raman spectroscopy. The results obtained can be used to optimize the growth technologies aimed to form structurally perfect short-period GaN/AlN SLs.
AB - We report the results of experimental and theoretical studies of phonon modes in GaN/AlN superlattices (SLs) with a period of several atomic layers, grown by submonolayer digital plasma-assisted molecular-beam epitaxy, which have a great potential for use in quantum and stress engi-neering. Using detailed group-theoretical analysis, the genesis of the SL vibrational modes from the modes of bulk AlN and GaN crystals is established. Ab initio calculations in the framework of the density functional theory, aimed at studying the phonon states, are performed for SLs with both equal and unequal layer thicknesses. The frequencies of the vibrational modes are calculated, and atomic displacement patterns are obtained. Raman spectra are calculated and compared with the experimental ones. The results of the ab initio calculations are in good agreement with the experimental Raman spectra and the results of the group-theoretical analysis. As a result of comprehensive studies, the correlations between the parameters of acoustic and optical phonons and the structure of SLs are obtained. This opens up new possibilities for the analysis of the structural characteristics of short-period GaN/AlN SLs using Raman spectroscopy. The results obtained can be used to optimize the growth technologies aimed to form structurally perfect short-period GaN/AlN SLs.
KW - Density functional theory
KW - GaN/AlN superlattices
KW - Group theory analysis
KW - Lattice dynamics
KW - Molecular beam epitaxy
KW - Raman spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=85099679568&partnerID=8YFLogxK
UR - https://www.mendeley.com/catalogue/a9998b54-000d-35fe-b8a8-9f06b9fd17dc/
U2 - 10.3390/nano11020286
DO - 10.3390/nano11020286
M3 - Article
AN - SCOPUS:85099679568
VL - 11
SP - 1
EP - 21
JO - Nanomaterials
JF - Nanomaterials
SN - 2079-4991
IS - 2
M1 - 286
ER -
ID: 74886371