# Active cluster crystals

## TL;DR

This paper investigates how self-propulsion affects the formation, deformation, and melting of cluster crystals in a 2D system of active Brownian particles with repulsive interactions, revealing the underlying physical mechanisms.

## Contribution

It introduces a detailed analysis of active cluster crystals, highlighting the impact of self-propulsion on cluster deformation and melting, using continuous field models.

## Key findings

- Self-propulsion deforms clusters by reducing internal particle density.
- High propulsion speeds lead to melting of the cluster crystal.
- Field models identify key physical mechanisms driving these effects.

## Abstract

We study the appearance and properties of cluster crystals (solids in which the unit cell is occupied by a cluster of particles) in a two-dimensional system of self-propelled active Brownian particles with repulsive interactions. Self-propulsion deforms the clusters by depleting particle density inside, and for large speeds it melts the crystal. Continuous field descriptions at several levels of approximation allow to identify the relevant physical mechanisms.