Dresden 2014 – wissenschaftliches Programm
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MM: Fachverband Metall- und Materialphysik
MM 34: Poster Session
MM 34.9: Poster
Dienstag, 1. April 2014, 18:00–20:00, P4
Heterogeneous shear elasticity of glasses: Instability, anharmonicity and fractional-power scaling — •Walter Schirmacher1,2, Alessia Marruzzo2,3, Andrea Fratalocchi3, Giancarlo Ruocco2, and Tullio Scopigno2 — 1Institut für Physik, Universität Mainz, Germany — 2Dipt. of Fisica, Universit’a "La Sapienza", Italy — 3Faculty of Electr. Eng., Applied Mathematics and Computational Science, King Abdullah University of Science and Technology, Saudi Arabia
Dynamical heterogeneity is the hallmark of glassy dynamics both on the liquid and on the solid side of the glass transition. On the solid side elastic heterogeneity causes a wealth of anomalous vibrational phenomena such as an enhancement of the vibrational spectrum over the Debye expectation (“boson peak”) and anomalous sound dispersion and attenuation. Above the boson peak frequency region the anomalies are entirely due to harmonic degrees of freedom and are caused by the disorder-induced breakdown of translational invariance. Below this region - as we report here by comparing experimental sound attenuation data with simulations on a soft-sphere glass and an appropriate theory - there develops a dynamical scaling scenario caused by the combined action of disorder, local instability and anharmonicity.