Contribución oral: Structural Evidence of Dynamic Reorganization in Vortex Matter into Partially Disordered Lattices

M. ESKILDSEN; M. MARZIALI BERMÚDEZ; G. PASQUINI; V. BEKERIS

Fethye

Conferencia; 5th International Conference on Superconductivity and Magnetism; 2016

Ordered phases are characterized by spatial correlations decaying weakly over distances larger than the relevant system scale, whereas disordered configurations are characterized by correlation lengths  of the order of the mean interparticle distance a0. Configurations with intermediate degrees of disorder, strong enough to affect the system response, but still with  >> a0, have received attention recently. We report structural evidence of dynamic reorganization in vortex matter (VM) [1] in clean NbSe2 by joint small angle neutron scattering (SANS) and ac susceptibility measurements. In a transitional region, near the order-disorder transition, we find robust metaestable ?over-ordered? or ?over-disordered? configurations, prepared by controlling the system thermo-magnetic history. The application of oscillatory forces in this H-T intermediate region results in robust bulk vortex lattice configurations with an intermediate degree of disorder, independent of the initial state. These dynamically originated configurations [2] correlate with intermediate pinning responses previously observed [3], resolving a long-standing debate regarding the origin of such responses.References1. M. Marziali Bermúdez, M. R. Eskildsen, M. Bartkowiak, G. Nagy, V.Bekeris and G. Pasquini, Phys. Rev. Lett. 115, 067001 (2015).2. D. Pérez Daroca, G. Pasquini, G. S. Lozano, and V. Bekeris, Phys. Rev. B 84, 012508 (2011).3. G. Pasquini, D. Pérez Daroca, C. Chiliotte, G. S. Lozano, and V. Bekeris, Phys. Rev. Lett. 100, 247003 (2008).