Related Experiment Video
Updated: Mar 23, 2026
06:24
High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
7.0K
Macroscopic alignment of chromonic liquid crystals using patterned substrates.
Jeong Yeon Kim1, Karthik Nayani, Hyeon Su Jeong
1National Research Laboratory for Organic Opto-Electronic Materials, Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Korea. heetae@kaist.ac.kr.
Physical Chemistry Chemical Physics : PCCP
|March 31, 2016
Summary
Secondary sputtering lithography (SSL) enables stable alignment of lyotropic chromonic liquid crystals (LCLCs). Optimal groove amplitude (A) for LCLC alignment is half the wavelength (λ), preventing further gains beyond qA∼3.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Surface Science
Background:
- Lyotropic chromonic liquid crystals (LCLCs) exhibit complex self-assembly properties.
- Achieving stable, monodomain alignment of LCLCs is crucial for device applications but remains challenging.
- Existing alignment techniques often lack efficiency and long-term stability.
Purpose of the Study:
- To develop an efficient method for aligning LCLCs.
- To investigate the relationship between surface topography and LCLC anchoring strength.
- To establish optimization criteria for fabricating patterned surfaces for LCLC alignment.
Main Methods:
- Secondary sputtering lithography (SSL) was employed to create patterned surfaces.
- Monodomains of LCLCs were prepared using SSL.
- A generalized Berreman's theory was used to calculate LCLC anchoring energy on patterned surfaces.
Main Results:
- SSL successfully produced LCLCs with stable alignment lasting for days.
- Anchoring energy increased with groove amplitude (A) up to A = λ/2.
- Anchoring energy plateaued for groove parameters qA > 3, indicating diminishing returns for increased patterning.
Conclusions:
- SSL is an effective technique for achieving stable monodomain alignment of LCLCs.
- Surface pattern geometry, specifically groove amplitude relative to wavelength, is critical for optimizing LCLC alignment.
- The study provides a quantitative criterion for designing patterned substrates to overcome alignment challenges in LCLCs.
