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Updated: Mar 13, 2026
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Electric-field-induced lamellar to hexagonally perforated lamellar transition in diblock copolymer thin films:
Arnab Mukherjee1, Kumar Ankit2, Andreas Reiter2
1Institute of Materials and Processes, Karlsruhe University of Applied Sciences, Moltkestr. 30, 76133, Karlsruhe, Germany. muar0002@hs-karlsruhe.de and Institute of Applied Materials - Computational Materials Science, Karlsruhe Institute of Technology, Haid-und-Neu str. 7, 76131, Karlsruhe, Germany.
Abstract:
Symmetric block-copolymers, hitherto, are well known to evolve into parallel, perpendicular and mixed lamellar morphologies under the concomitant influence of an electric field and substrate affinity. In the present work, we show that an additional imposed confinement can effectuate a novel parallel lamellar to hexagonally perforated lamellar (HPL) transition in monolayer and bilayer films. Three dimensional numerical studies are performed using the Ohta-Kawasaki functional, complemented with an exact solution of Maxwell's equation. HPL is shown to stabilize at large substrate affinity in a narrow region of the phase diagram between parallel and perpendicular lamellar transitions in ultra-thin films. Additionally, we also identify perforated lamellae as intermediate structures during parallel-to-perpendicular lamellar transition. A systematic analysis using Minkowski functionals yields deeper insights into the associated kinetic pathways.
