%0 Journal Article
%T Polarized Raman spectroscopy of v-SiO2 under rare-gas compression
%+ Laboratoire Charles Coulomb (L2C)
%+ Institut de minéralogie et de physique des milieux condensés (IMPMC)
%A Weigel, Coralie
%A Foret, Marie
%A Hehlen, Bernard
%A Kint, Mathieu
%A Clement, Sebastien
%A Polian, Alain
%A Vacher, Rene
%A Ruffle, Benoit
%< avec comité de lecture
%Z L2C:16-085
%@ 2469-9950
%J Physical Review B
%I American Physical Society
%V 93
%P 224303
%8 2016-06-20
%D 2016
%R 10.1103/PhysRevB.93.224303
%Z Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]Journal articles
%X High-pressure polarized Raman spectra of vitreous silica are measured up to 8 GPa in a diamond-anvil cell atroom temperature. The combined use of either a nonpenetrating pressurizing medium—argon—or a penetrating one—helium, allows one to separate density from stress effects on the Raman frequencies. In the framework of a simple central force model, the results emphasize the distinct role played by the shrinkage of the intertetrahedral angle Si-O-Si and the force-constant stiffening during the compression. The polarization analysis further reveals the existence of an additional isotropic component in the high-frequency wing of the boson peak. The pressure dependence of the genuine boson peak frequency is found to be much weaker than previously reported and even goes through a minimum around 2 GPa in remarkable coincidence with the anomalous compressibility maximum of silica.
%G English
%L hal-01337959
%U https://hal.science/hal-01337959
%~ UNIV-PARIS7
%~ UPMC
%~ CNRS
%~ IMPMC
%~ ALLINSP
%~ L2C
%~ USPC
%~ UPMC_POLE_2
%~ MIPS
%~ UNIV-MONTPELLIER
%~ SORBONNE-UNIVERSITE
%~ SU-SCIENCES
%~ UNIV-PARIS
%~ ALLIANCE-SU
%~ UM-2015-2021