Suppression of hyperuniformity in hydrodynamic scalar active field theories

J Phys Condens Matter. 2024 Dec 20. doi: 10.1088/1361-648X/ada243. Online ahead of print.

Abstract

The coarsening dynamics at late times in phase-separating systems lead to universally hyperuniform patterns. This is well known for scalar field theories, such as the Cahn-Hilliard equation, but has also been shown for dry scalar active field theories. We demonstrate the role of hydrodynamic interactions in influencing hyperuniformity in a wet active system described by active model H. Our direct numerical simulations reveal that, while (passive) model H shows hyperuniformity in the coarsening regime, the interplay of activity and hydrodynamic interactions suppresses hyperuniformity in active model H, especially when the activity generates contractile stress in the fluid.

Keywords: active field theories; hydrodynamics; hyperuniformity.