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Tasinkevych M, Park S, Mundoor H, Smalyukh II. Nanoparticle localization within chiral liquid crystal defect lines and nanoparticle interactions. Phys Rev E 2023; 107:034701. [PMID: 37073031 DOI: 10.1103/physreve.107.034701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 02/21/2023] [Indexed: 04/20/2023]
Abstract
Self-assembly of colloidal particles into predefined structures is a promising way to design inexpensive manmade materials with advanced macroscopic properties. Doping of nematic liquid crystals (LCs) with nanoparticles has a series of advantages in addressing these grand scientific and engineering challenges. It also provides a very rich soft matter platform for the discovery of unique condensed matter phases. The LC host naturally allows the realization of diverse anisotropic interparticle interactions, enriched by the spontaneous alignment of anisotropic particles due to the boundary conditions of the LC director. Here we demonstrate theoretically and experimentally that the ability of LC media to host topological defect lines can be used as a tool to probe the behavior of individual nanoparticles as well as effective interactions between them. LC defect lines irreversibly trap nanoparticles enabling controlled particle movement along the defect line with the use of a laser tweezer. Minimization of Landau-de Gennes free energy reveals a sensitivity of the ensuing effective nanoparticle interaction to the shape of the particle, surface anchoring strength, and temperature, which determine not only the strength of the interaction but also its repulsive or attractive character. Theoretical results are supported qualitatively by experimental observations. This work may pave the way toward designing controlled linear assemblies as well as one-dimensional crystals of nanoparticles such as gold nanorods or quantum dots with tunable interparticle spacing.
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Affiliation(s)
- Mykola Tasinkevych
- SOFT Group, School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS, United Kingdom
- Departamento de Física, and Centro de Física Teórica e Computacional, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
- International Institute for Sustainability with Knotted Chiral Meta Matter, Hiroshima University, Higashihiroshima 739-8511, Japan
| | - Sungoh Park
- Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
| | - Haridas Mundoor
- Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
| | - Ivan I Smalyukh
- International Institute for Sustainability with Knotted Chiral Meta Matter, Hiroshima University, Higashihiroshima 739-8511, Japan
- Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
- Soft Materials Research Center; Department of Electrical, Computer, and Energy Engineering and Materials Science and Engineering Program; and Renewable and Sustainable Energy Institute, National Renewable Energy Laboratory, University of Colorado, Boulder, Colorado 80309, USA
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Bhardwaj A, Sridurai V, Meleth Puthoor N, Nair GG. Enhanced Mie resonance in a low refractive index colloidal metamaterial aided by nematic liquid crystal. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2021.117116] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Liu X, Chen Z, Liu Q, Sheetah GH, Sun N, Zhao P, Xie Y, Smalyukh II. Morphological and Orientational Controls of Self-Assembly of Gold Nanorods Directed by Evaporative Microflows. ACS APPLIED MATERIALS & INTERFACES 2021; 13:53143-53154. [PMID: 34711053 DOI: 10.1021/acsami.1c12594] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Evaporative self-assembly of noble metal nanoparticles into ordered structures holds great promise for fabricating optical and plasmonic devices by virtue of its low cost, high efficiency, and ease of operation. However, poor control of Marangoni flows is one of the challenges accounting for realizing a well-defined assembly. Herein, based on the theoretical analysis of the influence of evaporative intensity on the assembly, two simple but reliable flow-field-confinement platforms are designed to control the evaporative microflows and to work concurrently with depletion forces to enable the regulated self-assembly of gold nanorods. Orientationally ordered assemblies are realized by the designed strong unidirectional microflow in a capillary, and a device-scale assembly of monolayer membrane is obtained by the created weak convection in homemade glass cells. Morphologically diversified superstructure assemblies, such as spherulite-like, boundary-twisted, chiral spiral assemblies, and merging membranes with a π-twisted domain wall, are obtained due to the spontaneous symmetry breaking or in the presence of defects, such as surface steps and screw dislocations. Optical anisotropy and polarization-dependent behaviors of these assemblies are further revealed, implying the potential applications in plasmonic coupling devices and optoelectronic components. An understanding of the entropy-driven assembly behaviors and control of evaporative microflows to guide the self-assembly of gold nanorods provides insights into the general bottom-up approach that is helpful for constructing complex yet robust nanosuperstructures.
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Affiliation(s)
- Xiaoduo Liu
- School of Physics, Beihang University, Beijing 100191, China
| | - Ziyu Chen
- School of Physics, Beihang University, Beijing 100191, China
| | - Qingkun Liu
- Department of Physics, Material Science and Engineering Program, Department of Electrical, Computer, & Energy Engineering, and Liquid Crystal Materials Research Center, University of Colorado, Boulder, Colorado 80309, United States
- Department of Physics, Cornell University, Ithaca, New York 14850, United States
| | - Ghadah H Sheetah
- Physics Department, College of Science, King Faisal University, Hofuf 31982, Saudi Arabia
| | - Ningfei Sun
- School of Physics, Beihang University, Beijing 100191, China
| | - Peng Zhao
- School of Physics, Beihang University, Beijing 100191, China
| | - Yong Xie
- School of Physics, Beihang University, Beijing 100191, China
- Key Laboratory of Intelligent Systems and Equipment Electromagnetic Environment Effect, School of Electronic and Information Engineering, Beihang University, Beijing 100191, China
| | - Ivan I Smalyukh
- Department of Physics, Material Science and Engineering Program, Department of Electrical, Computer, & Energy Engineering, and Liquid Crystal Materials Research Center, University of Colorado, Boulder, Colorado 80309, United States
- Renewable and Sustainable Energy Institute, National Renewable Energy Laboratory and University of Colorado, Boulder, Colorado 80309, United States
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Smalyukh II. Review: knots and other new topological effects in liquid crystals and colloids. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2020; 83:106601. [PMID: 32721944 DOI: 10.1088/1361-6633/abaa39] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Humankind has been obsessed with knots in religion, culture and daily life for millennia, while physicists like Gauss, Kelvin and Maxwell already involved them in models centuries ago. Nowadays, colloidal particles can be fabricated to have shapes of knots and links with arbitrary complexity. In liquid crystals, closed loops of singular vortex lines can be knotted by using colloidal particles and laser tweezers, as well as by confining nematic fluids into micrometer-sized droplets with complex topology. Knotted and linked colloidal particles induce knots and links of singular defects, which can be interlinked (or not) with colloidal particle knots, revealing the diversity of interactions between topologies of knotted fields and topologically nontrivial surfaces of colloidal objects. Even more diverse knotted structures emerge in nonsingular molecular alignment and magnetization fields in liquid crystals and colloidal ferromagnets. The topological solitons include hopfions, skyrmions, heliknotons, torons and other spatially localized continuous structures, which are classified based on homotopy theory, characterized by integer-valued topological invariants and often contain knotted or linked preimages, nonsingular regions of space corresponding to single points of the order parameter space. A zoo of topological solitons in liquid crystals, colloids and ferromagnets promises new breeds of information displays and a plethora of data storage, electro-optic and photonic applications. Their particle-like collective dynamics echoes coherent motions in active matter, ranging from crowds of people to schools of fish. This review discusses the state of the art in the field, as well as highlights recent developments and open questions in physics of knotted soft matter. We systematically overview knotted field configurations, the allowed transformations between them, their physical stability and how one can use one form of knotted fields to model, create and imprint other forms. The large variety of symmetries accessible to liquid crystals and colloids offer insights into stability, transformation and emergent dynamics of fully nonsingular and singular knotted fields of fundamental and applied importance. The common thread of this review is the ability to experimentally visualize these knots in real space. The review concludes with a discussion of how the studies of knots in liquid crystals and colloids can offer insights into topologically related structures in other branches of physics, with answers to many open questions, as well as how these experimentally observable knots hold a strong potential for providing new inspirations to the mathematical knot theory.
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Affiliation(s)
- Ivan I Smalyukh
- Department of Physics, Department of Electrical, Computer and Energy Engineering, Materials Science and Engineering Program and Soft Materials Research Center, University of Colorado, Boulder, CO 80309, United States of America
- Renewable and Sustainable Energy Institute, National Renewable Energy Laboratory and University of Colorado, Boulder, CO 80309, United States of America
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Hess A, Funk AJ, Liu Q, De La Cruz JA, Sheetah GH, Fleury B, Smalyukh II. Plasmonic Metamaterial Gels with Spatially Patterned Orientational Order via 3D Printing. ACS OMEGA 2019; 4:20558-20563. [PMID: 31858040 PMCID: PMC6906772 DOI: 10.1021/acsomega.9b02418] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 11/04/2019] [Indexed: 05/08/2023]
Abstract
Optical properties can be programmed on mesoscopic scales by patterning host materials while ordering their nanoparticle inclusions. While liquid crystals are often used to define the ordering of nanoparticles dispersed within them, this approach is typically limited to liquid crystals confined in classic geometries. In this work, the orientational order that liquid crystalline colloidal hosts impose on anisotropic nanoparticle inclusions is combined with an additive manufacturing method that enables engineered, macroscopic three-dimensional (3D) patterns of co-aligned gold nanorods and cellulose nanocrystals. These gels exhibit polarization-dependent plasmonic properties that emerge from the unique interaction between the host medium's anisotropic optical properties defined by orientationally ordered cellulose nanocrystals, from the liquid crystal's gold nanorod inclusions, and from the complexity of spatial patterns accessed with 3D printing. The gels' optical properties that are defined by the interplay of these effects are tuned by controlling the gels' order, which is tuned by adjusting the gels' cellulose nanocrystal concentrations. Lithe optical responsiveness of these composite gels to polarized radiation may enable unique technological applications like polarization-sensitive optical elements.
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Affiliation(s)
- Andrew
J. Hess
- Department
of Physics, 390 UCB, University of Colorado
Boulder, Boulder, Colorado 80309, United States
| | - Andrew J. Funk
- Department
of Physics, 390 UCB, University of Colorado
Boulder, Boulder, Colorado 80309, United States
| | - Qingkun Liu
- Department
of Physics, 390 UCB, University of Colorado
Boulder, Boulder, Colorado 80309, United States
| | - Joshua A. De La Cruz
- Materials
Science and Engineering, 027 UCB, Sustainability, Energy & Environment
Community, University of Colorado Boulder, Boulder, Colorado 80303, United States
| | - Ghadah H. Sheetah
- Materials
Science and Engineering, 027 UCB, Sustainability, Energy & Environment
Community, University of Colorado Boulder, Boulder, Colorado 80303, United States
| | - Blaise Fleury
- Department
of Physics, 390 UCB, University of Colorado
Boulder, Boulder, Colorado 80309, United States
| | - Ivan I. Smalyukh
- Department
of Physics, 390 UCB, University of Colorado
Boulder, Boulder, Colorado 80309, United States
- Materials
Science and Engineering, 027 UCB, Sustainability, Energy & Environment
Community, University of Colorado Boulder, Boulder, Colorado 80303, United States
- Renewable
and Sustainable Energy Institute, National
Renewable Energy Laboratory and University of Colorado, Boulder, Colorado 80309, United States
- E-mail:
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Santos RD, Melo PD, Nunes A, Meneghetti M, Lyra M, Oliveira ID. Electro-optical switching in twisted nematic samples doped with gold nanorods. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.111704] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Perspectives in Liquid-Crystal-Aided Nanotechnology and Nanoscience. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9122512] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The research field of liquid crystals and their applications is recently changing from being largely focused on display applications and optical shutter elements in various fields, to quite novel and diverse applications in the area of nanotechnology and nanoscience. Functional nanoparticles have recently been used to a significant extent to modify the physical properties of liquid crystals by the addition of ferroelectric and magnetic particles of different shapes, such as arbitrary and spherical, rods, wires and discs. Also, particles influencing optical properties are increasingly popular, such as quantum dots, plasmonic, semiconductors and metamaterials. The self-organization of liquid crystals is exploited to order templates and orient nanoparticles. Similarly, nanoparticles such as rods, nanotubes and graphene oxide are shown to form lyotropic liquid crystal phases in the presence of isotropic host solvents. These effects lead to a wealth of novel applications, many of which will be reviewed in this publication.
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Allie S, Hegoburu I, Shin MJ, Jung JY, Toader V, Rey A, Soule ER, Reven L. Polymer functionalized nanoparticles in liquid crystals: combining PDLCs with LC nanocomposites. SOFT MATTER 2018; 14:8580-8589. [PMID: 30318545 DOI: 10.1039/c8sm01192c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Liquid crystal (LC)-polymer blends are important stimuli responsive materials already employed in a wide range of applications whereas nanoparticle (NP)-LC blends are an emerging class of nanocomposites. Polymer ligands offer the advantages of synthetic simplicity along with chemical and molecular weight tunability. Here we compare the phase behavior of 5CB blended with poly(ethylene oxide) (PEO) and with gold NPs functionalized with thiolated PEO (AuNP-PEO) as a function of PEO concentration by DSC, POM and 13C NMR spectroscopy. Both PEO and the AuNP-PEO form uniform dispersions in isotropic 5CB and phase separate below the I-N phase transition temperature. Above the PEO crystallization temperature, the PEO/5CB blends show the expected biphasic state of PEO rich-isotropic liquid co-existing with PEO-poor nematic droplets. At PEO concentrations above 10 wt%, nematic 5CB nucleates with PEO crystallization. Both PEO and AuNP-PEO induce homeotropic alignment of the 5CB matrix immediately below TNI. The AuNP-PEO/5CB blends form thermally reversible cellular networks similar to AuNPs functionalized with low molecular weight mesogenic ligands. A thermodynamic model to account for the observed phase behavior is presented.
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Affiliation(s)
- Safiya Allie
- Quebec Centre for Advanced Materials, Department of Chemistry, McGill University, 801 Sherbrooke St. W., Montreal QC H3A 0B8, Canada.
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Sheetah GH, Liu Q, Senyuk B, Fleury B, Smalyukh II. Electric switching of visible and infrared transmission using liquid crystals co-doped with plasmonic gold nanorods and dichroic dyes. OPTICS EXPRESS 2018; 26:22264-22272. [PMID: 30130921 DOI: 10.1364/oe.26.022264] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 08/02/2018] [Indexed: 05/27/2023]
Abstract
Smart windows and many other applications require synchronous or alternating facile electric switching of transmitted light intensity in visible and near infrared spectral ranges, but most electrochromic devices suffer from slow, nonuniform switching, high power consumption and limited options for designing spectral characteristics. Here we develop a guest-host mesostructured composite with rod-like dye molecules and plasmonic nanorods spontaneously aligned either parallel or orthogonally to the director of the liquid crystal host. This composite material enables fast, low-voltage electric switching of electromagnetic radiation in visible and infrared ranges, which can be customized depending on the needs of applications, like climate-dependent optimal solar gain control in smart windows.
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Mundoor H, Sheetah GH, Park S, Ackerman PJ, Smalyukh II, van de Lagemaat J. Tuning and Switching a Plasmonic Quantum Dot "Sandwich" in a Nematic Line Defect. ACS NANO 2018; 12:2580-2590. [PMID: 29489324 DOI: 10.1021/acsnano.7b08462] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We study the quantum-mechanical effects arising in a single semiconductor core/shell quantum dot (QD) controllably sandwiched between two plasmonic nanorods. Control over the position and the "sandwich" confinement structure is achieved by the use of a linear-trap liquid crystal (LC) line defect and laser tweezers that "push" the sandwich together. This arrangement allows for the study of exciton-plasmon interactions in a single structure, unaltered by ensemble effects or the complexity of dielectric interfaces. We demonstrate the effect of plasmonic confinement on the photon antibunching behavior of the QD and its luminescence lifetime. The QD behaves as a single emitter when nanorods are far away from the QD but shows possible multiexciton emission and a significantly decreased lifetime when tightly confined in a plasmonic "sandwich". These findings demonstrate that LC defects, combined with laser tweezers, enable a versatile platform to study plasmonic coupling phenomena in a nanoscale laboratory, where all elements can be arranged almost at will.
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Affiliation(s)
| | | | | | | | - Ivan I Smalyukh
- Renewable and Sustainable Energy Institute , National Renewable Energy Laboratory and University of Colorado , Boulder , Colorado 80309 , United States
| | - Jao van de Lagemaat
- Renewable and Sustainable Energy Institute , National Renewable Energy Laboratory and University of Colorado , Boulder , Colorado 80309 , United States
- National Renewable Energy Laboratory , Golden , Colorado 80401 , United States
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11
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Wang Q, Liu L, Xu L. Coupling free energy and surface anchoring mechanism in gold nanorod–nematic liquid crystal dispersions. RSC Adv 2018. [DOI: 10.1039/c7ra09378k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Dependence of both the induced optical birefringence signals and simulated free energy ftotal with the pump H.
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Affiliation(s)
- Qi Wang
- Key Lab for Micro and Nanophotonic Structures (Ministry of Education)
- Department of Optical Science and Engineering
- School of Information Science and Engineering
- Fudan University
- Shanghai 200433
| | - Liying Liu
- Key Lab for Micro and Nanophotonic Structures (Ministry of Education)
- Department of Optical Science and Engineering
- School of Information Science and Engineering
- Fudan University
- Shanghai 200433
| | - Lei Xu
- Key Lab for Micro and Nanophotonic Structures (Ministry of Education)
- Department of Optical Science and Engineering
- School of Information Science and Engineering
- Fudan University
- Shanghai 200433
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Silva RS, de Melo PB, Omena L, Nunes AM, da Silva MGA, Meneghetti MR, de Oliveira IN. Temperature dependence of the nonlinear optical response of smectic liquid crystals containing gold nanorods. Phys Rev E 2017; 96:062703. [PMID: 29347296 DOI: 10.1103/physreve.96.062703] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Indexed: 06/07/2023]
Abstract
The present study is devoted to the investigation of the nonlinear optical properties of a smectic liquid crystal doped with gold nanorods. Using the Z-scan technique, we investigate the changes in the optical birefringence of a homeotropic sample upon laser exposure, considering the configurations of normal and oblique incidence. Our results reveal that the birefringence variations may be governed by distinct physical mechanisms, depending on the relative angle between the far-field director and the wave vector of the excitation laser beam. In particular, we observe that the position dependence of the far-field transmittance exhibits different behaviors as the incidence angle is changed, indicating that distortions in the beam wavefront may be associated with the thermal lens phenomenon or an optically induced reorientation of the nematic director. The temperature dependence of the nonlinear refractive and absorptive coefficients is investigated close to the smectic-A-nematic phase transition. A detailed analysis of the interplay between smectic order and plasmon resonance is performed, thus unveiling the capability of plasmonic liquid crystal to be used in optical devices.
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Affiliation(s)
- R S Silva
- Instituto de Física, Universidade Federal de Alagoas, 57072-970 Maceió, Alagoas, Brazil
| | - P B de Melo
- Instituto de Física, Universidade Federal de Alagoas, 57072-970 Maceió, Alagoas, Brazil
| | - L Omena
- Instituto de Física, Universidade Federal de Alagoas, 57072-970 Maceió, Alagoas, Brazil
| | - A M Nunes
- Instituto de Química e Biotecnologia, Universidade Federal de Alagoas, 57072-970 Maceió, Alagoas, Brazil
| | - M G A da Silva
- Instituto de Química e Biotecnologia, Universidade Federal de Alagoas, 57072-970 Maceió, Alagoas, Brazil
| | - M R Meneghetti
- Instituto de Química e Biotecnologia, Universidade Federal de Alagoas, 57072-970 Maceió, Alagoas, Brazil
| | - I N de Oliveira
- Instituto de Física, Universidade Federal de Alagoas, 57072-970 Maceió, Alagoas, Brazil
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Abstract
Skyrmions are topologically protected continuous field configurations that cannot be smoothly transformed to a uniform state. They behave like particles and give origins to the field of skyrmionics that promises racetrack memory and other technological applications. Unraveling the non-equilibrium behavior of such topological solitons is a challenge. We realize skyrmions in a chiral liquid crystal and, using numerical modeling and polarized video microscopy, demonstrate electrically driven squirming motion. We reveal the intricate details of non-equilibrium topology-preserving textural changes driving this behavior. Direction of the skyrmion’s motion is robustly controlled in a plane orthogonal to the applied field and can be reversed by varying frequency. Our findings may spur a paradigm of soliton dynamics in soft matter, with a rich interplay between topology, chirality, and orientational viscoelasticity. A skyrmion is a topological object originally introduced to model elementary particles and a baby skyrmion is its two-dimensional counterpart which can be realized as a defect in liquid crystals. Here the authors show that an electric field can drive uniform motion of baby skyrmions in liquid crystals.
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Ryu SH, Yoon DK. Switchable Plasmonic Film Using Nanoconfined Liquid Crystals. ACS APPLIED MATERIALS & INTERFACES 2017; 9:25057-25061. [PMID: 28677393 DOI: 10.1021/acsami.7b07693] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Structural coloration using plasmonic particles has received substantial attention due to its robust, permanent, and scalable characteristics across the full color range. In this study, a plasmonic structure based on a porous anodic aluminum oxide (AAO) film coated with a metallic film was fabricated. Colors were varied by changing the refractive index, which was achieved with a convolution with nanopores of AAO film and an infiltrated liquid crystal (LC) material. LC molecules confined in the porous AAO film were uniformly aligned, and they exhibited pore-size-dependent colors because of the specific refractive index. The thermal phase transition of the LC material in the nanopores changed the effective refractive index, switching the reflected colors, and the LC-infiltrated AAO remained stable over a month. We believe LC materials can extend the use of rigid conventional plasmonic structures from simple sensor applications to multifunctional uses such as color printing, writing pens, and displays.
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Affiliation(s)
- Seong Ho Ryu
- Graduate School of Nanoscience and Technology and KINC, KAIST , Daejeon 34141, Republic of Korea
| | - Dong Ki Yoon
- Graduate School of Nanoscience and Technology and KINC, KAIST , Daejeon 34141, Republic of Korea
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