Ref HAL: hal-00085972_v1
PMID 14995638
DOI: 10.1103/PhysRevE.69.011705
WoS: 000188946500042
Exporter : BibTex | endNote
21 Citations
Résumé:

An array of edge dislocation forms spontaneously in a Grandjean-Cano wedge filled by a smectic liquid crystal. In the vicinity of the smectic A to smectic C transition, these defects are visible under the microscope [R. B. Meyer, B. Stebler, and S. T. Lagerwall, Phys. Rev. Lett. 41, 1393 (1978)]. This paper deals with their dynamics under controlled deformation (dilation and compression). First, we characterize several regimes of dislocation mobility occurring with increasing strain epsilon or strain rate epsilon. We relate these regimes to the interactions between screw and edge dislocations. We also show that screw dislocations give rise to loops of edge dislocations under sufficient strain, which strengthens the model of loop nucleation by helical instability of screw dislocations. Lastly, we discuss several models for the microscopic origin of the interactions between defects.