The Mixing of Polarizations in the Acoustic Excitations of Disordered Media With Local Isotropy
Artikel i vetenskaplig tidskrift, 2018

An approximate solution of the Dyson equation related to a stochastic Helmholtz equation, which describes the acoustic dynamics of a three-dimensional isotropic random medium with elastic tensor fluctuating in space, is obtained in the framework of the Random Media Theory. The wavevector-dependence of the self-energy is preserved, thus allowing a description of the acoustic dynamics at wavelengths comparable with the size of heterogeneity domains. This in turn permits to quantitatively describe the mixing of longitudinal and transverse dynamics induced by the medium's elastic heterogeneity and occurring at such wavelengths. A functional analysis aimed to attest the mathematical coherence and to define the region of validity in the frequency-wavector plane of the proposed approximate solution is presented, with particular emphasis dedicated to the case of disorder characterized by an exponential decay of the covariance function.

mixing of polarizations

disordered systems

random media theory

Dyson equation

glasses

acoustic excitations

Författare

Maria G. Izzo

Istituto Italiano di Tecnologia

Sapienza, Università di Roma

Giancarlo Ruocco

Sapienza, Università di Roma

Istituto Italiano di Tecnologia

Stefano Cazzato

Chalmers, Fysik, Kondenserade materiens fysik

Sapienza, Università di Roma

FRONTIERS IN PHYSICS

2296-424X (ISSN)

Vol. 6 108

Ämneskategorier

Beräkningsmatematik

Annan fysik

Matematisk analys

DOI

10.3389/fphy.2018.00108

Mer information

Senast uppdaterat

2019-01-02