Anderson localization and reentrant delocalization of tensorial elastic waves in two-dimensional fractured media

TL;DR

This paper investigates how tensorial elastic waves behave in two-dimensional fractured media, revealing transitions from propagation to diffusion, localization, and reentrant delocalization influenced by fracture connectivity and stiffness.

Contribution

It uncovers the phenomena of reentrant delocalization and multifractality in elastic wave transport within fractured media, highlighting the role of network connectivity and mode conversion.

Findings

Waves are propagative at high fracture stiffness.

Waves become diffusive or localized at low stiffness depending on network connectivity.

Reentrant delocalization occurs due to energy leakage and mode conversion in well-connected networks.

Abstract

We study two-dimensional tensorial elastic wave transport in densely fractured media and document transitions from propagation to diffusion and to localization/delocalization. For large fracture stiffness, waves are propagative at the scale of the system. For small stiffness, multiple scattering prevails, such that waves are diffusive in disconnected fracture networks, and localized in connected ones with a strong multifractality of the intensity field. A reentrant delocalization is found in well-connected networks due to energy leakage via evanescent waves and cascades of mode conversion.