We report on the fabrication and characterization of curved periodic microstructures formed through the controlled phase separation of a liquid crystal and a polymerizing matrix comprising self-aligned liquid crystal. Imaging through a "Fresnel like" structure imparts an intensity profile onto a photosensitive mixture which subsequently forms periodic alternating curved polymeric and liquid crystal slices. The phase separated concentric rings of nematic liquid crystal self-align in a radial alignment in between the polymer walls as indicated by polarizing optical microscopy analysis (Maltese cross). Electro-optical experiments confirm the possibility to control this alignment and the optical properties of the macroscopic structure by means of a quite low external voltage. The system exhibits high-quality and self-alignment of an ordered (liquid crystal) fluid without the need of surface chemistry or functionalization. © 2014 AIP Publishing LLC.
Spontaneous radial liquid crystals alignment on curved polymeric surfaces / De Sio, Luciano; Tabiryan, Nelson; Bunning, Timothy. - In: APPLIED PHYSICS LETTERS. - ISSN 0003-6951. - 104:22(2014), p. 221112. [10.1063/1.4881976]
Spontaneous radial liquid crystals alignment on curved polymeric surfaces
De Sio, Luciano
;
2014
Abstract
We report on the fabrication and characterization of curved periodic microstructures formed through the controlled phase separation of a liquid crystal and a polymerizing matrix comprising self-aligned liquid crystal. Imaging through a "Fresnel like" structure imparts an intensity profile onto a photosensitive mixture which subsequently forms periodic alternating curved polymeric and liquid crystal slices. The phase separated concentric rings of nematic liquid crystal self-align in a radial alignment in between the polymer walls as indicated by polarizing optical microscopy analysis (Maltese cross). Electro-optical experiments confirm the possibility to control this alignment and the optical properties of the macroscopic structure by means of a quite low external voltage. The system exhibits high-quality and self-alignment of an ordered (liquid crystal) fluid without the need of surface chemistry or functionalization. © 2014 AIP Publishing LLC.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.