TY  - JOUR
AU  - Corley-Wiciak, Agnieszka Anna
AU  - Chen, Shunda
AU  - Concepción, Omar
AU  - Zoellner, Marvin Hartwig
AU  - Grützmacher, Detlev
AU  - Buca, Dan
AU  - Li, Tianshu
AU  - Capellini, Giovanni
AU  - Spirito, Davide
TI  - Local Alloy Order in a Ge 1 − x Sn x / Ge Epitaxial Layer
JO  - Physical review applied
VL  - 20
IS  - 2
SN  - 2331-7019
CY  - College Park, Md. [u.a.]
PB  - American Physical Society
M1  - FZJ-2024-01643
SP  - 024021
PY  - 2023
AB  - The local ordering of atoms in alloys directly has a strong impact on their electronic and opticalproperties. This is particularly relevant in nonrandom alloys, especially if they are deposited far fromthe equilibrium processes, as is the case for epitaxial Ge1−xSnx layers. In this work, we investigate thearrangement of Ge and Sn atoms in optoelectronic grade Ge1−xSnx epitaxial layers featuring a Sn contentin the 5–14% range by using polarization-dependent Raman spectroscopy and density-functional-theorycalculations. The thorough analysis of the polarization-dependent spectra in parallel and perpendicularconfiguration allowed us to properly tag all the observed vibrational modes, and to shed light on that associatedto disorder-assisted Raman transitions. Indeed, with the help of large-scale atomistic simulations,we were able to highlight how the presence of Sn atoms, that modify the local environments of Ge atoms,gives rise to two spectral features at different Raman shifts, corresponding to distortions of the atomicbonds. This analysis provides a valuable framework for advancing the understanding of the vibrationalproperties in Ge1−xSnx alloys, particularly with regard to the impact of local ordering of the differentatomic species.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:001052945100001
DO  - DOI:10.1103/PhysRevApplied.20.024021
UR  - https://juser.fz-juelich.de/record/1023070
ER  -