Current research interest lies in the interface between statistical and condensed matter physics. With main tools coming from computational physics (Monte Carlo, Langevin, molecular dynamics simulation techniques) we target different topics in condensed matter physics. These subjects covers problems within the spin and structural glasses classical point of view, domain walls motion in ferromagnetic and ferroelectric materials and stripes formation in thin magnetic films. [IMAGE]

  • Formation of stripes in magnetic systems.
  • Dynamical and spatial heterogeneities in spin glasses
  • Statics and dynamics of elastic lines in disorder media
  • Formation of stripes in magnetic systems.

            In collaboration with a research team at the Magnetic Resonance Lab at CAB, we are currently investigating the formation and stability of magnetic stripe domains in FeGa thin films. Under certain conditions, and after applying an in-plane magnetic field, some samples present an out-of-plane stripe domains structure. This structure can appear in a zig-zag pattern, never observed in this type of materials. We are now investigating the origin of these stripes domains.

    [IMAGE] [IMAGE]

    Dynamical and spatial heterogeneities in spin glasses.

            Using the concept of backbone structure we have identified the spatial heterogeneities giving place to the heterogeneous dynamical behavior observed in the two- and three-dimensional bimodal Edwards-Anderson spin glasses. The backbone structure, which is obtained from information given by the ground state topology, gives information on the ferromagnetic-like behavior of different spins in the system. This also naturally leads to the idea of a growth process within the backbone structure. We are now interested in how this idea can be generalized to other spin glass models with non-degenerate ground states such as the Gaussian Edwards-Anderson spin glass model. [IMAGE]

    Statics and dynamics of elastic lines in disorder media

    General aspects of the static and dynamical properties of elastic manifolds in disordered media are investigated. The studied topics include the out-of-equilibrium dynamics of vortex glasses and related models, thermal effects in the deppining of magnetic domain walls, and the geometrical properties of ferroelectric domain walls.

  • Thermal rounding of the depinning transition
  •         We have been investigating different aspects related to thermal effects in the properties of elastic lines in disordered media. We are particularly interested in the thermal rounding of the depinning transition, where we have intensively studied the power law of the velocity response with temperature exactly at the depinning threshold. We are also interested in thermal effects in the creep and static regimes. Other aspects such as the random-manifold to random-periodic crossover or the maximum relative height statistics have been investigated. [IMAGE] [IMAGE]

  • Domain walls in ferroelectric materials
  •         We are currently investigating the geometrical properties of artificially written domain walls in ferroelectric PZT samples. The experimental team at the DPMC, University of Geneva, are using a PFM microscope with ultra-high vacuum in order to write and characterize ferroelectric domain walls. We generated and analyzed numerical data that complement and help understanding the experimental results. [IMAGE]

  • Vecinal surfaces and single-file diffusion
  • Recently, we have investigated different aspects of the dynamics of steps in vecinal surfaces and its relation with the single-file diffusion problem. In particular we have studied the response of a surface step under a sudden quench of external conditions.

  • Out of equilibrium dynamics of elastic lines
  • We have studied in detail the dynamical properties of the vortex glass in high-temperature superconductors and its relation with the out-of-equilibrium dynamics of the Edwards-Wilkinson and Kardar-Parisi-Zhang equations.