Measuring order in the isotropic packing of elastic rods

Elsa Bayart (1) , S. Deboeuf (1, 2) , F. Corson (3) , A. Boudaoud (3, 4) , Mohktar Adda-Bedia (3)

1 LPS - Laboratoire de Physique Statistique de l'ENS
2 Department of Physics [McGill University]
3 LPS - Laboratoire de Physique Statistique de l'ENS
4 RDP - Reproduction et développement des plantes

The packing of elastic bodies has emerged as a paradigm for the study of macroscopic disordered systems. However, progress is hampered by the lack of controlled experiments. Here we consider a model experiment for the isotropic two-dimensional confinement of a rod by a central force. We seek to measure how ordered is a folded configuration and we identify two key quantities. A geometrical characterization is given by the number of superposed layers in the configuration. Using temporal modulations of the confining force, we probe the mechanical properties of the configuration and we define and measure its effective susceptibility. These two quantities may be used to build a statistical framework for packed elastic systems.

Mots clés: 46.32.+x -Static buckling and instability 46.70.Hg -Membranes; rods; and strings 61.43.-j -Disordered solids

Domaines: Mécanique statistique [cond-mat.stat-mech]; Adaptation et Systèmes auto-organisés [nlin.AO]

Elsa Bayart, S. Deboeuf, F. Corson, A. Boudaoud, Mohktar Adda-Bedia. Measuring order in the isotropic packing of elastic rods. EPL - Europhysics Letters, 2011, 95 (3), pp.34002. ⟨10.1209/0295-5075/95/34002⟩. ⟨hal-03025256⟩