Characterization of non-equilibrium melting in a 2D crystal

Here we study how a non-equilibrium 2D crystal undergoes melting as a function of activity. We use a system of charged particles confined to an oil-water interface forming a 2D lattice, a fraction of which have additional magnetic particles that sit directly below them and are rotated by an external magnetic field. This activity allows for the proliferation of topological defects, leading to melting of the 2D crystal. We characterize the nature of this melting transition and determine its order using conventional tools such as g₆(r) and the local distribution of Ψ₆. In addition, we use information theoretic approaches such as the computable information density (CID) and calculation of entropy production to gain further insight into the behavior of this non-equilibrium melting transition.