Active dumbbells: dynamics and morphology in the coexisting region

TL;DR

This study uses molecular dynamics simulations to explore the phase behavior of active dumbbells with purely repulsive interactions, revealing continuous transitions among liquid, hexatic, and solid phases as activity increases.

Contribution

It provides a detailed phase diagram and characterizes the structural and dynamical properties of active dumbbells, highlighting the continuous nature of phase transitions in the coexisting region.

Findings

Identification of liquid, hexatic, and solid phases in active dumbbells

Continuous phase transitions with increasing activity

Structural and dynamical properties vary smoothly across phases

Abstract

With the help of molecular dynamics simulations we study an ensemble of active dumbbells in purely repulsive interaction. We derive the phase diagram in the density-activity plane and we characterise the various phases with liquid, hexatic and solid character. The analysis of the structural and dynamical properties, such as enstrophy, mean square displacement, polarisation, and correlation functions, shows the continuous character of liquid and hexatic phases in the coexisting region when the activity is increased starting from the passive limit.