Shape instabilities of islands in smectic films under lateral compression. Issue 16 (6th April 2022)

• Record Type: Journal Article
• Authors: Missaoui, Amine; Harth, Kirsten; Trittel, Torsten; Klopp, Christoph; Stannarius, Ralf; Lacaze, Emmanuelle
• Is Part Of: Soft matter. Volume 18:Issue 16(2022)
• Page Start: 3193
• Page End: 3205
• Publication Date: 2022-04-06
• Subjects: Soft condensed matter -- Periodicals; 530.413
• DOI: 10.1039/d2sm00144f
• Languages: English
• ISSNs: 1744-683X

Abstract

Abstract : Freely suspended smectic liquid-crystal films are quasi-2D fluids, but under certain conditions, they behave like thin solid sheets. Abstract : Smectic liquid crystals are fluids, and in most rheological situations they behave as such. Nevertheless, when thin freely floating films of smectic A or smectic C materials are compressed quickly in-plane, they resist such stress by buckling similar to solid membranes under lateral stress. We report experimental observations of wrinkling and bulging of finite domains within the films, so-called islands, and give a qualitative explanation of different observed patterns. Depending on the external stress and their dimensions, the islands can expel a specifically shaped bulge in their center, form radial wrinkles or develop target-like wrinkle structures. When the external stress is relaxed, these patterns disappear reversibly.