title: Two-dimensional melting of a crystal of ferrofluid spikes.
abstract: We report the observation of the transition from an ordered solidlike phase to a disordered liquidlike phase of a lattice of spikes on a ferrofluid surface submitted to horizontal sinusoidal vibrations. The melting transition occurs for a critical spike displacement which is experimentally found to follow the Lindemann criterion, for two different lattice topologies (hexagonal and square) and over a wide range of lattice wavelengths. An intermediate hexaticlike phase between the solid and isotropic liquid phases is also observed and characterized by standard correlation functions. This dissipative out-of-equilibrium system exhibits strong similarities with 2D melting in solid-state physics.
authors.affiliation: IUSTI, Université de Provence, CNRS (UMR 6595), 5 rue E. Fermi, 13 453 Marseille, France.
authors.forename: François
authors.initials: F
authors.lastname: Boyer
authors.forename: Eric
authors.initials: E
authors.lastname: Falcon