Decay Dynamics of a Single Spherical Domain in Near-Critical Phase-Separated Conditions

Area of Science:

• Physical Chemistry
• Materials Science

Background:

• Domain decay is central to Ostwald ripening in phase ordering kinetics.
• Large domains grow by consuming smaller ones, a process termed evaporation-condensation.

Purpose of the Study:

• To experimentally investigate single domain decay dynamics.
• To reconcile observed decay with theoretical predictions, particularly concerning surface tension.
• To understand the influence of gravity on domain decay.

Main Methods:

• Optomechanical manipulation of single spherical domains in a near-critical binary liquid mixture.
• Experimental observation of domain decay dynamics.
• Mean-field theoretical description to account for experimental observations.

Main Results:

• Observed domain decay dynamics deviate from standard surface-tension decay laws.
• Gravity-induced solute concentration gradients explain the deviation near critical points.
• Identified conditions where buoyancy is negligible compared to capillarity.
• Experimental validation of surface-tension driven decay exponent under specific conditions.

Conclusions:

• Single domain decay dynamics are influenced by gravity-induced concentration gradients.
• Surface-tension driven decay can be isolated and experimentally verified by minimizing gravitational effects.
• This work establishes the fundamental surface-tension driven decay mechanisms in conserved order parameter systems, with and without gravity.