Elementary Edge and Screw Dislocations Visualized at the Lattice Periodicity Level in the Smectic Phase of Colloidal Rods

Andrii Repula, Eric Grelet
2018 Physical Review Letters  
We report on the identification and quantitative characterization of elementary edge and screw dislocations in a colloidal smectic phase of tip-labeled rods. Thanks to the micrometer layer spacing, direct visualization of dislocations has been performed at the smectic periodicity scale by optical fluorescence microscopy. As a result, the displacement field around an edge dislocation has been experimentally established and compared with the profile predicted by elastic theory. Elementary screw
more » ... slocations have been also evidenced, for which the core size as well as the in situ handedness have been determined. Self-diffusion experiments performed at the individual particle level reveal for the first time nematic-like or "melted" ordering of the defect core.
doi:10.1103/physrevlett.121.097801 pmid:30230877 fatcat:wtxvluqj6bfxjcqjsghq2xrt3a