Deutsche Tagung f ¨ur Forschung mit ... - SNI-Portal

Struktur und Dynamik Poster: Mi., 14:00–16:30 M-P152
Relation between the excess density of states and Brillouin spectra in glasses
Walter Schirmacher 1 , Giancarlo Ruocco 2 , Tullio Scopigno 2
1 Phys. Dept. E13, TU München, D-5747 Garching, Germany – 2 Dipt. di Fisica, Uni-
versit’a La Sapienza, I00185 Roma, Italy
Using a theory developed recently by one of us, based on a model in which the shear
modulus exhibits a random spatial variation due to the disorder, we derive relations
between the excess of the density of vibrational states and the position and width of
the Brillouin peak observed in inelastic X-ray, neutron and light scattering. Comparing
these relations with results of molecular-dynamics simulations and experiments gives
good agreement with the theory.