Observation of macro-heterogeneities in surface-stabilized smectic C* with antagonistically patterned substrates

A.A. Kudreyko1, W. Song2, D.N. Migranova3
1Ufa State Petroleum Technological University
2Shanghai University of Engineering Sciences
3East Economic-Legal Humanitarian Academy


Geometry of the surface-stabilized FLC cell.In our recent study, we theoretically considered equilibrium states in a monolayered sample of ferroelectric liquid crystal in smectic C* phase, confined between two differently patterned substrates with strong anchoring under the applied electric field. By using the continuum theory for a “bookshelf” aligned sample for smectic C*, we derived elliptic sine-Gordon equation. The solution of the Dirichlet problem has shown that due to the antagonistic boundary conditions at the substrates, competing boundary effects in the thin film generate a stable alignment of smectic C* director. This alignment can be controlled by the electric field. Our theoretical finding was described as the system with harmonically coupled “atoms” with external potential within the framework of the Frenkel-Kontorova model. To challenge our finding, we prepared a cell with differently patterned substrates, and ferroelectric liquid crystal material CS-1024 (Chisso Co.) was injected into the empty cell by the capillarity flow. Patterned monolayers exhibiting planar alignment of CS-1024 in its smectic C* phase were created using microcontact printing of functionalized organothiols on gold films. By patterning the surface with planar alignment of monolayers, the location and formation of smectic C* director macro-heterogeneities can be controlled by the electric field. The observed macro-heterogeneities continue to exist when the electric field is turned off. Polarizing microscopy and fluorescent microscopy were used to observe the formation of macro-heterogeneities in the alignment of SmC* director field.

Received: 06 July 2017   Revised: 29 September 2017   Accepted: 02 October 2017

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S. T. Lagerwall. Ferroelectric and Antiferroelectric Liquid Crystals. Weinheim, Wiley-VCH, (1999) 63 p. DOI: 10.1002/9783527613588.ch3
A. A. Kudreyko, N. G. Migranov, D. N. Migranova. Nonlin. Phen. Compl. Sys. 19 (1), 95 – 101 (2016).
O. M. Braun, Y. S. Kivshar. Phys. Rep. 306, 1 – 108 (1998). DOI: 10.1016/S0370-1573(98)00029-5
A. A. Kudreyko, N. G. Migranov, D. N. Migranova. Rus. Phys. J. 59 (7), 938 – 943 (2016). DOI: 10.1007/s11182-016-0857-x
I. W. Stewart. The Static and Dynamic Continuum Theory of Liquid Crystals. A Mathematical Introduction. New York, Taylor & Francis, (2004), 306 p.
S. V. Kalinin, D. A. Bonnell, T. Alvarez, X. Lei, Z. Hu, R. Shao, J. H. Ferris. Adv. Mater. 16 (9-10), 795 – 799 (2004). DOI: 10.1002/adma.200305702
H. Matthias, H.‑S. Kitzerow. Mol. Cryst. Liq. Cryst. 508, 127 [489] – 136 [498] (2009). DOI: 10.1080/15421400903060300
K. Rijeesh, H. Higuchi, Y. Okumura, J. Yamamoto, H. Kikuchi. Polymer 116 (5), 447 – 451 (2017). DOI: 10.1016/j.polymer.2016.12.012
I. Dierking, M. Mitov, M. A. Osipov. Soft Matter 11 (5), 819 – 837 (2015). DOI: 10.1039/c4sm02505a
A. Jakli, A. Saupe. Appl. Phys. Lett. 60, 2622 – 2624 (1992). DOI: 10.1063/1.106900