title: Entanglement and the nonlinear elastic behavior of forests of coiled carbon nanotubes.
abstract: Helical or coiled nanostructures have been objects of intense experimental and theoretical studies due to their special electronic and mechanical properties. Recently, it was experimentally reported that the dynamical response of a foamlike forest of coiled carbon nanotubes under mechanical impact exhibits a nonlinear, non-Hertzian behavior, with no trace of plastic deformation. The physical origin of this unusual behavior is not yet fully understood. In this Letter, based on analytical models, we show that the entanglement among neighboring coils in the superior part of the forest surface must be taken into account for a full description of the strongly nonlinear behavior of the impact response of a drop ball onto a forest of coiled carbon nanotubes.
authors: Instituto de Física "Gleb Wataghin," Universidade Estadual de Campinas, C.P. 6165, 13083-970 Campinas SP, Brazil. coluci@ifi.unicamp.br
authors: V R
authors: VR
authors: Coluci
authors: A F
authors: AF
authors: Fonseca
authors: D S
authors: DS
authors: Galvão
authors: C
authors: C
authors: Daraio