Flexoelectricity in Liquid Crystals

Flexoelectricity in Liquid Crystals
Author: Agnes Buka
Publisher: World Scientific
Total Pages: 299
Release: 2013
Genre: Science
ISBN: 1848167997

The book intends to give a state-of-the-art overview of flexoelectricity, a linear physical coupling between mechanical (orientational) deformations and electric polarization, which is specific to systems with orientational order, such as liquid crystals. Chapters written by experts in the field shed light on theoretical as well as experimental aspects of research carried out since the discovery of flexoelectricity. Besides a common macroscopic (continuum) description the microscopic theory of flexoelectricity is also addressed. Electro-optic effects due to or modified by flexoelectricity as well as various (direct and indirect) measurement methods are discussed. Special emphasis is given to the role of flexoelectricity in pattern-forming instabilities. While the main focus of the book lies in flexoelectricity in nematic liquid crystals, peculiarities of other mesophases (bent-core systems, cholesterics, and smectics) are also reviewed. Flexoelectricity has relevance to biological (living) systems and can also offer possibilities for technical applications. The basics of these two interdisciplinary fields are also summarized.

Electrooptic Effects in Liquid Crystal Materials

Electrooptic Effects in Liquid Crystal Materials
Author: L.M. Blinov
Publisher: Springer Science & Business Media
Total Pages: 477
Release: 2012-12-06
Genre: Science
ISBN: 1461226929

Electrooptic effects provide the basis for much liquid-crystal display technology. This book, by two of the leaders in liquid-crystal research in Russia, presents a complete and accessible treatment of virtually all known phenomena occurring in liquid crystals under the influence of electric fields.

Structure and Properties of Liquid Crystals

Structure and Properties of Liquid Crystals
Author: Lev M. Blinov
Publisher: Springer Science & Business Media
Total Pages: 448
Release: 2010-10-26
Genre: Science
ISBN: 9048188296

This book by Lev M. Blinov is ideal to guide researchers from their very first encounter with liquid crystals to the level where they can perform independent experiments on liquid crystals with a thorough understanding of their behaviour also in relation to the theoretical framework. Liquid crystals can be found everywhere around us. They are used in virtually every display device, whether it is for domestic appliances of for specialized technological instruments. Their finely tunable optical properties make them suitable also for thermo-sensing and laser technologies. There are many monographs written by prominent scholars on the subject of liquid crystals. The majority of them presents the subject in great depth, sometimes focusing on a particular research aspect, and in general they require a significant level of prior knowledge. In contrast, this books aims at an audience of advanced undergraduate and graduate students in physics, chemistry and materials science. The book consists of three parts: the first part, on structure, starts from the fundamental principles underlying the structure of liquid crystals, their rich phase behaviour and the methods used to study them; the second part, on physical properties, emphasizes the influence of anisotropy on all aspects of liquid crystals behaviour; the third, focuses on electro-optics, the most important properties from the applications standpoint. This part covers only the main effects and illustrates the underlying principles in greater detail. Professor Lev M. Blinov has had a long carrier as an experimentalist. He made major contributions in the field of ferroelectric mesophases. In 1985 he received the USSR state prize for investigations of electro-optical effects in liquid crystals for spatial light modulators. In 1999 he was awarded the Frederiks medal of the Soviet Liquid Crystal Society and in 2000 he was honoured with the G. Gray silver medal of the British Liquid Crystal Society. He has held many visiting academic positions in universities and laboratories across Europe and in Japan.

Fundamentals of Liquid Crystal Devices

Fundamentals of Liquid Crystal Devices
Author: Deng-Ke Yang
Publisher: John Wiley & Sons
Total Pages: 588
Release: 2014-12-03
Genre: Technology & Engineering
ISBN: 1118752007

Liquid Crystal Devices are crucial and ubiquitous components of an ever-increasing number of technologies. They are used in everything from cellular phones, eBook readers, GPS devices, computer monitors and automotive displays to projectors and TVs, to name but a few. This second edition continues to serve as an introductory guide to the fundamental properties of liquid crystals and their technical application, while explicating the recent advancements within LCD technology. This edition includes important new chapters on blue-phase display technology, advancements in LCD research significantly contributed to by the authors themselves. This title is of particular interest to engineers and researchers involved in display technology and graduate students involved in display technology research. Key features: Updated throughout to reflect the latest technical state-of-the-art in LCD research and development, including new chapters and material on topics such as the properties of blue-phase liquid crystal displays and 3D liquid crystal displays; Explains the link between the fundamental scientific principles behind liquid crystal technology and their application to photonic devices and displays, providing a thorough understanding of the physics, optics, electro-optics and material aspects of Liquid Crystal Devices; Revised material reflecting developments in LCD technology, including updates on optical modelling methods, transmissive LCDs and tunable liquid crystal photonic devices; Chapters conclude with detailed homework problems to further cement an understanding of the topic.

Augmenting Electro-Optic and Optical Behavior of Cholesteric and Nematic Liquid Crystals

Augmenting Electro-Optic and Optical Behavior of Cholesteric and Nematic Liquid Crystals
Author: Andrii Varanytsia
Publisher:
Total Pages: 206
Release: 2018
Genre: Library of Congress Subject Heading
ISBN:

Commending topological defects of liquid crystals (LCs) facilitates many configurational simulations and experimental manipulations of active soft matter for electro-optical (EO), optical and photonic applications. In this dissertation, investigation of topological defects in cholesteric liquid crystals (CLCs) enables better visualizing and control unique self-assembly, dielectric and optical properties of CLCs and leads to the development of a fast switching active retarder film based on a CLC with uniform lying helix (ULH) texture, a bistable light diffractive CLC films based on metastable bubble domain (BD) texture, and an in-plane-switching (IPS) LC device based on two-dimensional graphene electrode.We first demonstrate a giant flexoelectro-optic effect (FOE) in a CLC with ULH texture. The electric-field-induced helical axis (HA) rotation of a ULH structure due to flexoelectric coupling is accomplished by the surface-localized polymer network stabilization. A 40 times enhancement in flexoelastic coefficient compared to a conventional CLC materials is achieved by using the CLC based on CB7CB bimesogen. The giant FOE of a polymer-stabilized ULH (PS-ULH) enables the development of an active retarder having high optical contrast and sub-millisecond response time.The second part of dissertation is to investigate topology-mediated optical and electro-optical properties of CLCs with BD texture (CLC-BD) providing unique bistability between the light transmission and light scattering states. The CLC-BD device requires electric field only during switching between transparent and opaque states creating great potential applications as active diffusers and smart windows. An opto-mechanical modulation is demonstrated with a light-sensitive chiral azo-benzene dye doping in a CLC-BD device. To close, the augmentation of EO behavior in a nematic IPS device with graphene transparent electrode is demonstrated. We command the EO switching on photo-lithographically-patterned graphene electrode with a highly-effective non-contact LC photoalignment method to maximize the field-driven optical contrast of a prototyped device. Our experiments provide a solution for technical challenges related to processing and handling of two-dimensional graphene on rigid and flexible substrates and facilitate the applications of graphene for devices with complex and high-definition electrode patterns.