Superadiabatic dynamical density functional study of Brownian hard-spheres in time-dependent external potentials

Area of Science:

• Statistical Mechanics
• Computational Physics
• Soft Matter Physics

Background:

• Understanding the dynamics of interacting particles is crucial in condensed matter physics.
• Traditional methods often require extensive simulations or adjustable parameters.
• Dynamical density functional theory (DDFT) offers a promising first-principles approach.

Purpose of the Study:

• To investigate the response of interacting Brownian particles to time-dependent external driving using superadiabatic-DDFT.
• To directly predict the dynamics of the one-body density from interparticle interactions.
• To compare superadiabatic-DDFT predictions with adiabatic DDFT and Brownian dynamics simulations.

Main Methods:

• Employed superadiabatic dynamical density functional theory (superadiabatic-DDFT), a first-principles approach.
• Utilized inhomogeneous two-body correlation functions to model particle interactions.
• Investigated external potentials designed to probe structural relaxation in dense liquids.

Main Results:

• Superadiabatic-DDFT accurately predicts the time-evolution of the one-body density for interacting Brownian particles.
• Predictions were made directly from interparticle interactions, without adjustable parameters or simulation input.
• Nonequilibrium density profiles from superadiabatic-DDFT showed good agreement with simulation data.

Conclusions:

• Superadiabatic-DDFT is a reliable and efficient first-principles method for studying nonequilibrium dynamics.
• The theory accurately captures the response of interacting particle systems to external driving.
• This approach provides a parameter-free alternative to traditional simulation methods.