Shape instabilities of islands in smectic films under lateral compression

• DOI: 10.1039/d2sm00144f
• Publication Date: 2022-04-06T08:37:21Z
• Authors: Amine Missaoui; Kirsten Harth; Torsten Trittel; Christoph Klopp; Ralf Stannarius; Emmanuelle Lacaze
• Keywords: Wrinkle

Smectic liquid crystals are fluids, and in most rheological situations they behave as such. Nevertheless, when thin freely floating films of smectic A or C materials compressed quickly in-plane, resist such stress by buckling similar to solid membranes under lateral stress. We report experimental observations wrinkling bulging finite domains within the films, so-called islands, give a qualitative explanation different observed patterns. Depending on external their dimensions, islands can expel specifically shaped bulge center, form radial wrinkles develop target-like wrinkle structures. When is relaxed, these patterns disappear reversibly.