NON-GAUSSIAN TAIL IN THE FORCE DISTRIBUTION: A HALLMARK OF CORRELATED DISORDER IN THE HOST MEDIA OF ELASTIC OBJECTS

FASANO, YANINA

Conferencia; Invited parallel talk in the International Conference on Strongly Correlated Electronic Systems (SCES)- virtual and quinquenal format; 2021

Inferring the nature of disorder in the media where elastic objects are nucleated is of crucial importance for many applications but remains a challenging basic-science problem. Here we propose a method to discern whether weak-point or string-correlated disorder dominates based on characterizing the distribution of the interaction forces between objects mapped in large fields-of-view. We illustrate our proposal with the case-study system of vortex structures nucleated in type-II superconductors with different pinning landscapes. Interaction force distributions are computed from individual vortex positions imaged in thousands-vortices fields-of-view in a two-orders-or-magnitude-wide vortex-density range. Vortex structures nucleated in point-disordered media present Gaussian distributions of the interaction force components. In contrast, if the media have dilute and randomly distributed correlated disorder, these distributions present non-Gaussian algebraically-decaying tails for large force magnitudes. We propose that detecting this deviation from the Gaussian behavior is a fingerprint of strong disorder, in our case originated from a dilute distribution of correlated centers.