Recent Progresses on Experimental Investigations of Topological and Dissipative Solitons in Liquid Crystals

Solitons in liquid crystals have received increasing attention due to their importance in fundamental physical science and potential applications in various fields. The study of solitons in liquid crystals has been carried out for over five decades with various kinds of solitons being reported. Recently, a number of new types of solitons have been observed, among which, many of them exhibit intriguing dynamic behaviors. In this paper, we briefly review the recent progresses on experimental investigations of solitons in liquid crystals.

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Azo-containing asymmetric bent-core liquid crystals with modulated smectic phases

RSC Advances ◽

10.1039/c5ra09764a ◽

2015 ◽

Vol 5 (80) ◽

pp. 64886-64891 ◽

Cited By ~ 12

Author(s):

Nemanja Trišović ◽

Jelena Antanasijević ◽

Tibor Tóth-Katona ◽

Michal Kohout ◽

Miroslaw Salamonczyk ◽

...

Keyword(s):

Liquid Crystals ◽

Synthesis And Characterization ◽

Temperature Range ◽

Smectic Phases ◽

Potential Applications

We present the synthesis and characterization of ten asymmetric bent-core liquid crystals with enantiotropic modulated smectic (B7 type) phases. Their relatively low and wide photosensitive mesomorphic temperature range offers potential applications.

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A new class of nonreciprocal spin waves on the edges of 2D antiferromagnetic honeycomb nanoribbons

Scientific Reports ◽

10.1038/s41598-019-51646-3 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 4

Author(s):

D. Ghader ◽

A. Khater

Keyword(s):

Spin Waves ◽

Experimental Studies ◽

Classical Field Theory ◽

Experimental Investigations ◽

Theory Approach ◽

Magnetic Excitations ◽

Spintronic Devices ◽

New Class ◽

Potential Applications ◽

Edge Spin

Abstract Antiferromagnetic two-dimensional (2D) materials are currently under intensive theoretical and experimental investigations in view of their potential applications in antiferromagnet-based magnonic and spintronic devices. Recent experimental studies revealed the importance of magnetic anisotropy and of Dzyaloshinskii-Moriya interactions (DMI) on the ordered ground state and the magnetic excitations in these materials. In this work we present a robust classical field theory approach to study the effects of anisotropy and the DMI on the edge and bulk spin waves in 2D antiferromagnetic nanoribbons. We predict the existence of a new class of nonreciprocal edge spin waves, characterized by opposite polarizations in counter-propagation. These novel edge spin waves are induced by the DMI and are fundamentally different from conventional nonreciprocal spin waves for which the polarization is independent of the propagation direction. We further analyze the effects of the edge structures on the magnetic excitations for these systems. In particular, we show that anisotropic bearded edge nanoribbons act as topologically trivial magnetic insulators with potentially interesting applications in magnonics. Our results constitute an important finding for current efforts seeking to establish unconventional magnonic devices utilizing spin wave polarization.

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Structural Stability of Functionalized Silicene Nanoribbons with Normal, Reconstructed, and Hybrid Edges

Journal of Nanomaterials ◽

10.1155/2016/5959162 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Sadegh Mehdi Aghaei ◽

Ingrid Torres ◽

Irene Calizo

Keyword(s):

Structural Stability ◽

First Principles ◽

Experimental Investigations ◽

First Principles Calculations ◽

Zigzag Edge ◽

Edge Structure ◽

Practical Applications ◽

Potential Applications ◽

Silicene Nanoribbons ◽

Significant Attention

Silicene, a novel graphene-like material, has attracted a significant attention because of its potential applications for nanoelectronics. In this paper, we have theoretically investigated the structural stability of edge-hydrogenated and edge-fluorinated silicene nanoribbons (SiNRs) via first-principles calculations. Various edge forms of SiNRs including armchair edge, zigzag edge, Klein edge, reconstructed Klein edge, reconstructed pentagon-heptagon edge, and hybrid edges have been considered. It has been found that fully fluorinated Klein edge SiNRs, in which each edge Si atom is terminated by three fluorine atoms, are the most stable structure. We also discovered that a hybrid edge structure of trihydrogenated Klein edge and dihydrogenated zigzag edge can increase the nanoribbon’s stability up to that of dihydrogenated armchair edge SiNR, which is known as the most stable edge-hydrogenated structure. With the attractive properties of silicene for practical applications, the obtained results will advance experimental investigations toward the development of silicene based devices.

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Current Advances in Ejector Modeling, Experimentation and Applications for Refrigeration and Heat Pumps. Part 2: Two-Phase Ejectors

Inventions ◽

10.3390/inventions4010016 ◽

2019 ◽

Vol 4 (1) ◽

pp. 16 ◽

Cited By ~ 5

Author(s):

Zine Aidoun ◽

Khaled Ameur ◽

Mehdi Falsafioon ◽

Messaoud Badache

Keyword(s):

Heat Pumps ◽

Operating Conditions ◽

Industrial Processes ◽

Experimental Investigations ◽

Mixing Enhancement ◽

Data Generation ◽

Two Phase ◽

Wide Range ◽

Potential Applications ◽

And Performance

Two-phase ejectors play a major role as refrigerant expansion devices in vapor compression systems and can find potential applications in many other industrial processes. As a result, they have become a focus of attention for the last few decades from the scientific community, not only for the expansion work recovery in a wide range of refrigeration and heat pump cycles but also in industrial processes as entrainment and mixing enhancement agents. This review provides relevant findings and trends, characterizing the design, operation and performance of the two-phase ejector as a component. Effects of geometry, operating conditions and the main developments in terms of theoretical and experimental approaches, rating methods and applications are discussed in detail. Ejector expansion refrigeration cycles (EERC) as well as the related theoretical and experimental research are reported. New and other relevant cycle combinations proposed in the recent literature are organized under theoretical and experimental headings by refrigerant types and/or by chronology whenever appropriate and systematically commented. This review brings out the fact that theoretical ejector and cycle studies outnumber experimental investigations and data generation. More emerging numerical studies of two-phase ejectors are a positive step, which has to be further supported by more validation work.

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Recent Advances in Integrated Photonic Jet-Based Photonics

Photonics ◽

10.3390/photonics7020041 ◽

2020 ◽

Vol 7 (2) ◽

pp. 41 ◽

Cited By ~ 4

Author(s):

Igor V. Minin ◽

Cheng-Yang Liu ◽

Yury E. Geints ◽

Oleg V. Minin

Keyword(s):

Side Surface ◽

Experimental Investigations ◽

Spatial Period ◽

Janus Particle ◽

Optical Wave ◽

Optical Scanning ◽

Potential Applications ◽

New Type ◽

Photonic Jet ◽

Shadow Side

The study of accelerating Airy-family beams has made significant progress, not only in terms of numerical and experimental investigations, but also in conjunction with many potential applications. However, the curvature of such beams (and hence their acceleration) is usually greater than the wavelength. Relatively recently, a new type of localized wave beams with subwavelength curvature, called photonic hooks, was discovered. This paper briefly reviews the substantial literature concerning photonic jet and photonic hook phenomena, based on the photonic jet principle. Meanwhile, the photonic jet ensemble can be produced by optical wave diffraction at 2D phase diffraction gratings. The guidelines of jets’ efficient manipulation, through the variation of both the shape and spatial period of diffraction grating rulings, are considered. Amazingly, the mesoscale dielectric Janus particle, with broken shape or refractive index symmetry, is used to generate the curved photonic jet—a photonic hook—emerging from its shadow-side surface. Using the photonic hook, the resolution of optical scanning systems can be improved to develop optomechanical tweezers for moving nanoparticles, cells, bacteria and viruses along curved paths and around transparent obstacles. These unique properties of photonic jets and hooks combine to afford important applications for low-loss waveguiding, subdiffraction-resolution nanopatterning and nanolithography.

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Ionic Liquid Crystals in Tribology

Lubricants ◽

10.3390/lubricants7090072 ◽

2019 ◽

Vol 7 (9) ◽

pp. 72 ◽

Cited By ~ 9

Author(s):

M.D. Avilés ◽

C. Sánchez ◽

R. Pamies ◽

J. Sanes ◽

M.D. Bermúdez

Keyword(s):

Molecular Structure ◽

Ionic Liquid ◽

Ionic Liquids ◽

Liquid Crystals ◽

Tribological Performance ◽

Wear Rates ◽

Fatty Acid Derivatives ◽

Potential Applications ◽

Ionic Liquid Crystals ◽

Definition Of

The present work intends to provide a brief account of the most recent advances in the use of ionic liquid crystals (ILCs) in the field of tribology, that is, the development of new lubricants with the ability to reduce the coefficients of friction and the wear rates of materials under sliding conditions. After a definition of ILCs and their relationship with neutral liquid crystals (LCs) and ionic liquids (ILs), the review will be focused on the influence of molecular structure and composition on the tribological performance, the combination with base oils, surfactants or water, and the different sliding configuration and potential applications. The main mechanisms proposed in order to justify the lubricating ability of ILCs will be analyzed. Special emphasis will be made for recent results obtained for fatty acid derivatives due to their renewable and environmentally friendly nature.

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Laser Assisted Machining: An Overview

Journal of Manufacturing Science and Engineering ◽

10.1115/1.2836822 ◽

1997 ◽

Vol 119 (4B) ◽

pp. 766-769 ◽

Cited By ~ 99

Author(s):

G. Chryssolouris ◽

N. Anifantis ◽

S. Karagiannis

Keyword(s):

Scientific Work ◽

Research Trends ◽

Experimental Investigations ◽

Laser Machining ◽

Relevant Research ◽

Research Topics ◽

Laser Technology ◽

Laser Assisted Machining ◽

Recent Developments ◽

Potential Applications

Since laser technology has considerable synergy with machining technologies, Laser Machining (LM) and Laser Assisted Machining (LAM) are relevant research topics. This paper attempts to give an overview of recent developments and research trends. Although scientific work on this area has contributed to the understanding of the process, there are still unresolved problems regarding the limitations of the techniques, optimum machining conditions, etc. The outcome of experimental investigations on LAM shows potential applications for this process but there are several issues to be resolved.

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Tunable Channel Drop Filter in a Two-Dimensional Photonic Crystal Modulated by a Nematic Liquid Crystal

Journal of Nanomaterials ◽

10.1155/jnm/2006/52946 ◽

2006 ◽

Vol 2006 ◽

pp. 1-6 ◽

Cited By ~ 7

Author(s):

Chen-Yang Liu ◽

Lien-Wen Chen

Keyword(s):

Liquid Crystals ◽

Integrated Circuits ◽

Wavelength Division Multiplexing ◽

Light Propagation ◽

Nematic Liquid Crystals ◽

Fdtd Method ◽

Wavelength Division ◽

Resonance Frequencies ◽

Potential Applications ◽

Control Light

Photonic crystals (PCs) have many potential applications because of their ability to control light-wave propagation and because PC-based waveguides may be integrated into optical circuits. We propose a novel tunable PC channel drop filter based on nematic liquid crystals and investigate its properties numerically by using the finite-difference time-domain (FDTD) method. The refractive indices of liquid crystals can be actively modulated after infiltrating nematic liquid crystals into the microcavity in PC waveguides with square lattices. Then we can control light propagation in a PC waveguide. We analyze theQ-factors and resonance frequencies of a tunable PC channel drop filter by considering various indices modulation of liquid crystals. The novel component can be used as wavelength division multiplexing in photonic integrated circuits.

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Perspectives in active liquid crystals

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2013.0373 ◽

2014 ◽

Vol 372 (2029) ◽

pp. 20130373 ◽

Cited By ~ 4

Author(s):

Apala Majumdar ◽

Marchetti M. Cristina ◽

Epifanio G. Virga

Keyword(s):

Liquid Crystals ◽

Spontaneous Activity ◽

Soft Matter ◽

Interested Reader ◽

Theme Issue ◽

New Class ◽

Active Liquid ◽

Potential Applications ◽

Non Equilibrium

Active soft matter is a young, growing field, with potential applications to a wide variety of systems. This Theme Issue explores this emerging new field by highlighting active liquid crystals. The collected contributions bridge theory to experiment, mathematical theories of passive and active nematics, spontaneous flows to defect dynamics, microscopic to continuum levels of description, spontaneous activity to biological activation. While the perspectives offered here only span a small part of this rapidly evolving field, we trust that they might provide the interested reader with a taste for this new class of non-equilibrium systems and their rich behaviour.

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