  We study the influence of a structural disorder on the thermodynamical
properties of 2D-elastic chains submitted to mechanical/topological constraint
as loops. The disorder is introduced via a spontaneous curvature whose
distribution along the chain presents either no correlation or long-range
correlations (LRC). The equilibrium properties of the one-loop system are
derived numerically and analytically for weak disorder. LRC are shown to favor
the formation of small loop, larger the LRC, smaller the loop size. We use the
mean first passage time formalism to show that the typical short time loop
dynamics is superdiffusive in the presence of LRC. Potential biological
implications on nucleosome positioning and dynamics in eukaryotic chromatin are
discussed.
