Article
Optics
Arturo Reyes-Romero, J. Adrian Reyes
Summary: In this study, a planar waveguide with a confined cholesteric liquid crystal was examined, and the electromagnetic equations describing the dynamics of propagating modes were solved numerically. The study revealed the propagating parameter and the ratio between magnetic and electric modes as a function of frequency, aligning with the band structure of the modes. The profiles of electromagnetic field amplitudes and the distribution of the Poynting vector were also calculated, along with a discussion on the embodiment of transverse electric and magnetic modes in the eigen modes and their propagation conditions.
OPTICS AND LASER TECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
Saddam Hussain, Soo-Young Park
Summary: The unique combination of photonic helicoidal structure and rubber-like properties in cholesteric liquid-crystal elastomers results in a highly stretchable mechanochromic film capable of reflecting both right- and left-handed circular polarized light. The patterned photonic CLCE film, controlled by applied strain, can encrypt data and camouflage itself under unpolarized daylight. These elastomers have potential applications in sensors, robotics, displays, encryption, and anti-counterfeiting due to their mechanochromic capabilities.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Optics
Yo Inoue, Hiroshi Moritake
Summary: A cholesteric liquid-crystal gel with fast and continuous wavelength shift is fabricated and demonstrated in a laser scanning device.
Article
Physics, Fluids & Plasmas
Akihiro Yamashita, Jun-ichi Fukuda
Summary: We numerically investigate the structure of twin boundaries in cholesteric blue phases. The study shows that the formation of twin boundaries is not prohibitively costly, consistent with previous experimental findings.
Article
Energy & Fuels
Amid Ranjkesh, Yeongyu Choi, Jae-Won Huh, Seung-Won Oh, Tae-Hoon Yoon
Summary: A flexible cholesteric liquid crystal (CLC) polymer reflector is proposed in this study to selectively control the reflection of infrared (IR) light, effectively lowering indoor temperature. The fabricated IR reflector demonstrates thinness, high mechanical stability, flexibility, durability, resistance to solvents and acids, high transparency, and low haze in visible light. This innovative approach shows promise for applications in anti-IR devices, energy-saving windows for cars, and modern building facades.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2021)
Article
Crystallography
Ho-Jin Sohn, Seung-Won Oh, Yeongyu Choi, Seong-Min Ji, Tae-Hoon Yoon
Summary: A simple fabrication method of a uniform-lying-helix cholesteric liquid crystal cell for phase grating device applications was demonstrated, achieving a large diffraction angle and low operating voltage by optimizing the cell gap. The diffraction efficiency of the ULH cell can be maximized with a given grating period.
Article
Chemistry, Multidisciplinary
Zhuohao Zhang, Zhuoyue Chen, Yu Wang, Yuanjin Zhao, Luoran Shang
Summary: This study introduces a novel composite cellulose cholesteric liquid crystals as a bionic prototype for biological structural coloration, allowing for color range adjustments and dynamic control. By incorporating polymer monomers and crosslinking polymers, a series of structural color materials with high-resolution patterns have been developed, showing potential applications in wearable sensors, graphic displays, and information encryption.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Xianjing Huang, Dong Zhu, Zhou Zhou, Kuixian Chen, Guoxing Zheng, Peng Chen, Yan-Qing Lu, Zile Li
Summary: Traditional holographic encryption methods based on the combination of gratings and liquid crystals (LCs) cannot provide full security due to the lack of strict requirements for decoding methods. In this paper, a simple but effective encryption method is proposed, and a four-in-one hologram based on photopatterned LCs is designed. The most important encrypted image can only be displayed when the four LC holograms in the same group are spliced into a whole according to the designed order. Our encryption scheme has the advantages of simple design, high security, and low crosstalk, with great potential in the fields of information hiding and image encryption.
Article
Physics, Multidisciplinary
Oswaldo Adapta, J. Adrian Reyes
Summary: This research investigates a planar waveguide made of a cholesteric liquid crystalline elastomer with a perpendicular helical axis to the planar boundaries. The electrodynamics equations and constitutive equations are established. The mechanical stress is adjusted through elastic deformations in order to control the propagation parameters. The resulting equation system is numerically solved assuming the guide to be surrounded by air or vacuum. The band structure of the electromagnetic modes and the mixing of transverse electric and magnetic modes within the waveguide are studied.
Article
Multidisciplinary Sciences
Zhuohao Zhang, Chong Wang, Qiao Wang, Yuanjin Zhao, Luoran Shang
Summary: In this study, a printable structural color ink composed of cholesteric cellulose liquid crystals, gelatin, and a thermal-responsive hydrogel is proposed. This ink exhibits angle-independent color appearances and possesses dual thermal responsiveness, making it a promising material for next-generation 3D printing with a wide range of real-life applications.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Materials Science, Multidisciplinary
Lotfi Saadaoui, Ridha Hamdi
Summary: This study investigated the pattern formation in planar-oriented Cholesteric Liquid Crystals (CLC) for various thicknesses to pitch (d/p) ratios, as well as the features of the director's fields and defects lines. Experimental results showed that the dynamic formation of grating stripes varied for different d/p ratios, with differences in stripe orientation and contrast evolution.
Article
Multidisciplinary Sciences
Oxana Prishchepa, Mikhail Krakhalev, Vladimir Rudyak, Vitaly Sutormin, Victor Zyryanov
Summary: This study focuses on the electro-optical cell based on cholesteric liquid crystal with unique boundary conditions, involving conical anchoring on one substrate and planar anchoring on another. The periodic structures within the cholesteric layer and their transformation under applied electric field are studied using polarizing optical microscopy and computational analysis. The research shows that by applying a voltage, the growth direction of the defect lines forming a diffraction grating can be controlled, with U+-defects moving along the lines when the voltage exceeds 1.3V.
SCIENTIFIC REPORTS
(2021)
Article
Chemistry, Physical
Yi-Cheng Chang, Sheng-Hsiung Yang, Victor Ya. Zyryanov, Wei Lee
Summary: We have demonstrated a cholesteric liquid crystal (CLC) smart window that can switch between transparent and low-transmission states reversibly based on thermo-optic effect. This smart window utilizes a thermoresponsive handedness-reversible chiral dopant in a mixture of chiral dopant, dichroic dye and nematic liquid crystal to create a thermosensitized CLC. By increasing the temperature, the device switches from a homeotropic texture to a fingerprint texture. The absorption characteristic of the dichroic dye enables the CLC to have two distinct transmission levels.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Chemistry, Physical
G. Negro, L. N. Carenza, G. Gonnella, D. Marenduzzo, E. Orlandini
Summary: We investigate the phase behavior of cholesteric liquid crystal shells with different geometries. Comparing cases of tangential anchoring and no anchoring, we focus on the former case where there is competition between the intrinsic tendency of the cholesteric to twist and the anchoring free energy that suppresses it. We then characterize the topological phases near the isotropic-cholesteric transition, which consist of quasi-crystalline or amorphous tessellations of the shell surface by half-skyrmions.
Article
Chemistry, Physical
Ahmad M. Labeeb, Yassmin A. Ward, Mohamed Fikry
Summary: This research article focuses on tunable photonic optical bandgap materials and devices based on cholesteric liquid crystals. Mixtures of different cholesteric liquid crystals were studied for their optical properties at various temperatures, with the optimum tuned bandgap observed in mixtures coded AMJ3 and AMJ4.
JOURNAL OF MOLECULAR LIQUIDS
(2021)
