Výsledky vyhledávání - "Vacher, René"

Report

Pressure-induced densification of vitreous silica: insight from elastic properties

Autor: Weigel, Coralie, Mebarki, Marouane, Clément, Sébastien, Vacher, René, Foret, Marie, Rufflé, Benoit

Publikováno v: Phys. Rev. B 100, 094102 (2019)

\textit{In situ} high-pressure Brillouin light scattering experiments along loading-unloading paths are used to investigate the compressibility of vitreous silica. An accurate equation of state is obtained below \SI{9}{GPa} using sound velocities cor

Externí odkaz: http://arxiv.org/abs/1901.02235

Zobrazit plný text záznamu

Report

Vitreous silica distends in helium gas: acoustic vs. static compressibilities

Autor: Weigel, Coralie, Polian, Alain, Kint, Mathieu, Rufflé, Benoit, Foret, Marie, Vacher, René

Publikováno v: Phys. Rev. Lett. 109 245504 (2012)

Sound velocities of vitreous silica are measured under He compression in the pressure range 0-6 GPa by Brillouin light scattering. It is found that the well-known anomalous maximum in the pressure dependence of the compressibility is suppressed by He

Externí odkaz: http://arxiv.org/abs/1302.1668

Zobrazit plný text záznamu

Report

Acoustic damping and dispersion in vitreous germanium oxide

Autor: Guimbretière, Guillaume, Rufflé, Benoît, Vacher, René

Publikováno v: Phys RevB 86 094304 (2012)

New Brillouin scattering measurements of velocity and attenuation of sound in the hypersonic regime are presented. The data are analyzed together with the literature results at sonic and ultrasonic frequencies. As usual, thermally activated relaxatio

Externí odkaz: http://arxiv.org/abs/1207.4582

Zobrazit plný text záznamu

Report

Small Angle Neutron Scattering of Aerogels: Simulations and Experiments

Autor: Hasmy, Anwar, Foret, Marie, Anglaret, Eric, Pelous, Jacques, Vacher, René, Jullien, Rémi

A numerical simulation of silica aerogels is performed using diffusion-limited cluster-cluster aggregation of spheres inside a cubic box (with periodic boundary conditions). The volume fraction $c$ is taken to be sufficiently large to get a gel struc

Externí odkaz: http://arxiv.org/abs/cond-mat/9504055

Zobrazit plný text záznamu

Report

Small Angle Scattering by Fractal Aggregates: A Numerical Investigation of the Crossover Between the Fractal Regime and the Porod Regime

Autor: Hasmy, Anwar, Vacher, René, Jullien, Rémi

Fractal aggregates are built on a computer using off-lattice cluster-cluster aggregation models. The aggregates are made of spherical particles of different sizes distributed according to a Gaussian-like distribution characterised by a mean $a_0$ and

Externí odkaz: http://arxiv.org/abs/cond-mat/9504053

Zobrazit plný text záznamu

High-frequency acoustic modes in silica via ultrafast optical techniques

Autor: Huynh, Agnès, Péronne, Emmanuel, Perrin, Bernard, Rufflé, Benoit, Vacher, René, Foret, Marie

Publikováno v: Forum Acusticum
Forum Acusticum, Dec 2020, Lyon, France. pp.1893-1893, ⟨10.48465/fa.2020.0723⟩

International audience; We use the advent of reliable ultrafast optical techniques to explore acoustic modes in glasses in the difficult but crucial frequency region between around 0.1 and 1 THz. Brillouin scattering of light allows to measure veloci

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ec7ac88b11b124a9f524d5fca59010a5

Zobrazit plný text záznamu