Eur. Phys. J. E (2018) 41: 73
https://doi.org/10.1140/epje/i2018-11684-9

Regular Article

Dislocations dynamics during the nonlinear creep of a homeotropic sample of smectic-A liquid crystal

Laboratoire de Physique, Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS, F-69342, Lyon, France

^* e-mail: patrick.oswald@ens-lyon.fr

Received: 27 April 2018
Accepted: 29 May 2018
Published online: 12 June 2018

Abstract

New creep experiments under sinusoidal compression/dilation deformation of a homeotropic sample of smectic-A liquid crystal (8CB) show that its response is nonlinear at very small amplitude of deformation. This behavior is explained by taking into account the crossing between the edge dislocations that climb parallel to the layers and the screw dislocations joining the two surfaces limiting the sample. The activation energy of the crossing process and the density of the screw dislocations as a function of the sample thickness are estimated experimentally.