Dissipation and velocity distribution at the shear-driven jamming transition.

Area of Science:

• Physics
• Soft Matter Physics
• Statistical Mechanics

Background:

• The jamming transition is a critical phenomenon where a system of particles loses fluidity and becomes solid-like.
• Understanding energy dissipation and particle dynamics near jamming is crucial for materials science and granular physics.
• Previous studies have explored static jamming, but shear-driven jamming dynamics require further investigation.

Purpose of the Study:

• To investigate energy dissipation mechanisms at the jamming transition.
• To analyze the distribution of particle velocities in shear-driven systems.
• To explore the behavior of frictionless disks in two dimensions at zero temperature.

Main Methods:

• Simulations of overdamped, shear-driven, frictionless disks in two dimensions.
• Analysis of energy dissipation and particle velocity distributions.
• Focus on the behavior as the system approaches the jamming transition.

Main Results:

• Energy dissipation is primarily caused by the fastest-moving particles.
• The fraction of particles responsible for dissipation decreases towards zero as jamming is approached.
• Particle velocities exhibit an algebraic tail distribution (∼v^{-3}) near jamming.
• Different velocity measures diverge uniquely, challenging conventional analytical approaches.

Conclusions:

• The fastest particles dominate energy dissipation at the jamming transition.
• The velocity distribution's algebraic tail provides insights into non-equilibrium dynamics.
• The differing divergences of velocity measures necessitate revised analytical frameworks for shear-driven jamming.