Commensurate and Incommensurate Vortex Lattice Melting in Periodic Pinning Arrays

Abstract

We examine the melting of commensurate and incommensurate vortex lattices interacting with square pinning arrays through the use of numerical simulations. For weak pinning strength in the commensurate case we observe an order-order transition from a commensurate square vortex lattice to a triangular floating solid phase as a function of temperature. This floating solid phase melts into a liquid at still higher temperature. For strong pinning there is only a single transition from the square pinned lattice to the liquid state. For strong pinning in the incommensurate case, we observe a multi-stage melting in which the interstitial vortices become mobile first, followed by the melting of the entire lattice, consistent with recent imaging experiments. The initial motion of vortices in the incommensurate phase occurs by an exchange process of interstitial vortices with vortices located at the pinning sites. We have also examined the vortex melting behavior for higher matching fields and find that a coexistence of a commensurate pinned vortex lattice with an interstitial vortex liquid occurs while at higher temperatures the entire vortex lattice melts. For triangular arrays at incommensurate fields higher than the first matching field we observe that the initial vortex motion can occur through a novel correlated ring excitation where a number of vortices can rotate around a pinned vortex. We also discuss the relevance of our results to recent experiments of colloidal particles interacting with periodic trap arrays.

8 figures

Cited by in corpus (26)

• Observation of Vortex Pinning in Bose-Einstein Condensates
• Superconducting Transition and Vortex Pinning in Nb Films Patterned with Nano-scale Hole-arrays
• Structural phase transitions of vortex matter in an optical lattice
• Vortex Molecular Crystal and Vortex Plastic Crystal States in Honeycomb and Kagome Pinning Arrays
• Mott insulator phases and first-order melting in BSCCO crystals with periodic surface holes
• Transport Anisotropy as a Probe of the Interstitial Vortex State in Superconductors with Artificial Pinning Arrays
• Rhombic preordering on a square substrate
• Ordering and Melting in Colloidal Molecular Crystal Mixtures
• Commensurate States and Pattern Switching via Liquid Crystal Skyrmions Trapped in a Square Lattice
• Manipulation of Vortices by Localized Impurities in Bose-Einstein Condensates
• Anisotropic Sliding Dynamics, Peak Effect, and Metastability in Stripe Systems
• Vortex patterns and the critical rotational frequency in rotating dipolar Bose-Einstein condensates
• Unusual magneto-transport of YBa2Cu3O7-d films due to the interplay of anisotropy, random disorder and nanoscale periodic pinning
• Vortices in layered superconductors with columnar pins: A density functional study
• Collective vortex phases in periodic plus random pinning potential
• Enhancement of mobilities in a pinned multidomain crystal
• Comparing the Dynamics of Skyrmions and Superconducting Vortices
• Frustration and Melting of Colloidal Molecular Crystals
• Vortex states in 2D superconductor at high magnetic field in a periodic pinning potential
• Heterogeneities and Topological Defects in Two-Dimensional Pinned Liquids
• Transport signatures of fragile-glass dynamics in the melting of the two-dimensional vortex lattice
• Continuous Melting of a "Partially Pinned" Two-Dimensional Vortex Lattice in a Square Array of Pinning Centers
• Active Matter on Asymmetric Substrates
• Rotational transition, domain formation, dislocations and defects in vortex systems with combined six- and 12-fold anisotropic interactions
• Transitions between phyllotactic lattice states in curved geometries
• Brownian dynamics study of driven partially pinned solid in the presence of square array of pinning centers: Enhanced pinning close to the melting transition