Tiling the plane with noncongruent toric focal conic domains
This paper deals with regular arrays of macroscopic defects (focal conic domains) observed when a slab of lamellar phase is sandwiched between two substrates imposing different orientational anchorings. We report, in particular, detailed observations of the texture of a lyotropic lamellar phase in contact with a glass substrate and a lyotropic sponge phase. We consider several models for the defects depending on the material and the substrate parameters. Their energy has a common form, and the main features of the textures are explained in the framework of a simple model where disks of different sizes tile a plane in order to minimize a particular interface energy.
Blanc
C
Laboratoire de Mineralogie-Cristallographie de Paris, CNRS UMR No. 7590, T16 case 115, Universite Pierre et Marie Curie, 4 Place Jussieu, F-75252 Paris Cedex 05, France.
Kleman
M