Phase order and energy localization in acoustic propagation in random bubbly liquids

Propagation of acoustic waves in liquid media containing many air-filled bu bbles is studied using a self-consistent approach. It is shown that under p roper conditions, multiple scattering leads to a peculiar phase transition in acoustic propagation. When the phase transition occurs, not only the aco ustic waves are confined in the neighborhood of the transmitting source, bu t a previously unsuspected collective behavior of the air bubbles appears, responsible for effective cancellation of the propagating wave. A novel pha se diagram method is used to depict the phase transition. (C) 2000 Elsevier Science B.V. All rights reserved.