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Ngo TT, Viaña JM, Romero M, Calvo ME, Lozano G, Míguez H. Enhancement of upconversion photoluminescence in phosphor nanoparticle thin films using metallic nanoantennas fabricated by colloidal lithography. MATERIALS ADVANCES 2023; 4:6381-6388. [PMID: 38021467 PMCID: PMC10680131 DOI: 10.1039/d3ma00775h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 10/31/2023] [Indexed: 12/01/2023]
Abstract
Lanthanide-doped upconversion nanoparticles (UCNPs), as multifunctional light sources, are finding utility in diverse applications ranging from biotechnology to light harvesting. However, the main challenge in realizing their full potential lies in achieving bright and efficient photon upconversion (UC). In this study, we present a novel approach to fabricate an array of gold nanoantennas arranged in a hexagonal lattice using a simple and inexpensive colloidal lithography technique, and demonstrate a significant enhancement of UC photoluminescence (UCPL) by up to 35-fold through plasmon-enhanced photoexcitation and emission. To elucidate the underlying physical mechanisms responsible for the observed UCPL enhancement, we provide a comprehensive theoretical and experimental characterization, including a detailed photophysical description and numerical simulations of the spatial electric field distribution. Our results shed light on the fundamental principles governing the enhanced UCNPs and pave the way for their potential applications in photonic devices.
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Affiliation(s)
- Thi Tuyen Ngo
- Institute of Materials Science of Seville, Spanish National Research Council - University of Seville, Américo Vespucio, 49 41092 Seville Spain
| | - Jose M Viaña
- Institute of Materials Science of Seville, Spanish National Research Council - University of Seville, Américo Vespucio, 49 41092 Seville Spain
| | - Manuel Romero
- Institute of Materials Science of Seville, Spanish National Research Council - University of Seville, Américo Vespucio, 49 41092 Seville Spain
| | - Mauricio E Calvo
- Institute of Materials Science of Seville, Spanish National Research Council - University of Seville, Américo Vespucio, 49 41092 Seville Spain
| | - Gabriel Lozano
- Institute of Materials Science of Seville, Spanish National Research Council - University of Seville, Américo Vespucio, 49 41092 Seville Spain
| | - Hernán Míguez
- Institute of Materials Science of Seville, Spanish National Research Council - University of Seville, Américo Vespucio, 49 41092 Seville Spain
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2
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Ruzzi V, Baglioni J, Piazza R. Optothermal crystallization of hard spheres in an effective bidimensional geometry. J Chem Phys 2023; 159:154904. [PMID: 37850694 DOI: 10.1063/5.0169221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 10/01/2023] [Indexed: 10/19/2023] Open
Abstract
Using colloids effectively confined in two dimensions by a cell with a thickness comparable to the particle size, we investigate the nucleation and growth of crystallites induced by locally heating the solvent with a near-infrared laser beam. The particles, which are "thermophilic," move towards the laser spot solely because of thermophoresis with no convection effects, forming dense clusters whose structure is monitored using two order parameters that gauge the local density and the orientational ordering. We find that ordering takes place when the cluster reaches an average surface density that is still below the upper equilibrium limit for the fluid phase of hard disks, meaning that we do not detect any sign of a proper "two-stage" nucleation from a glass or a polymorphic crystal structure. The crystal obtained at late growth stage displays a remarkable uniformity with a negligible amount of defects, arguably because the incoming particles diffuse, bounce, and displace other particles before settling at the crystal interface. This "fluidization" of the outer crystal edge may resemble the surface enhanced mobility giving rise to ultra-stable glasses by physical vapor deposition.
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Affiliation(s)
- Vincenzo Ruzzi
- Department of Chemistry, Materials Science, and Chemical Engineering (CMIC) "Giulio Natta," Politecnico di Milano, Edificio 6, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Jacopo Baglioni
- Department of Chemistry, Materials Science, and Chemical Engineering (CMIC) "Giulio Natta," Politecnico di Milano, Edificio 6, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Roberto Piazza
- Department of Chemistry, Materials Science, and Chemical Engineering (CMIC) "Giulio Natta," Politecnico di Milano, Edificio 6, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
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3
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Viaña JM, Romero M, Lozano G, Míguez H. Nanoantennas Patterned by Colloidal Lithography for Enhanced Nanophosphor Light Emission. ACS APPLIED NANO MATERIALS 2022; 5:16242-16249. [PMID: 36466302 PMCID: PMC9706497 DOI: 10.1021/acsanm.2c03258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 10/18/2022] [Indexed: 06/17/2023]
Abstract
Transparent coatings made of rare-earth doped nanocrystals, also known as nanophosphors, feature efficient photoluminescence and excellent thermal and optical stability. Herein, we demonstrate that the optical antennas prepared by colloidal lithography render thin nanophosphor films with a brighter emission. In particular, we fabricate gold nanostructures in the proximity of GdVO4:Eu3+ nanophosphors by metal evaporation using a mask made of a monolayer of polymer beads arranged in a triangular lattice. Optical modes supported by the antennas can be controlled by tuning the diameter of the polymer spheres in the colloidal mask, which determines the shape of the gold nanostructure, as confirmed by numerical simulations. Confocal microscopy reveals that metallic antennas induce brighter photoluminescence at specific spatial regions of the nanophosphor film at targeted frequencies as a result of the coupling between gold nanostructures and nanophosphors. Patterning of nanophosphor thin layers with arrays of metallic antennas offers an inexpensive nanophotonic solution to develop bright emitting coatings of interest for color conversion, labeling, or anti-counterfeiting.
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Dogra AR, Sharma V, Gahrotra R, Kumar P. Evaporation induced self-assembly of silica nanoparticles on ITO substrates in a confined cell for vertical alignment of liquid crystals and performance analysis. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.128712] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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5
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Gao Y, Zhou Y, Xu X, Chen C, Xiong B, Zhu J. Fabrication of Oriented Colloidal Crystals from Capillary Assembly of Polymer-Tethered Gold Nanoparticles. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2106880. [PMID: 35146905 DOI: 10.1002/smll.202106880] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 01/10/2022] [Indexed: 06/14/2023]
Abstract
Self-assembled colloidal crystals (CCs) or nanoparticle (NPs) superlattices have attracted significant attention due to their potential applications in many fields. However, due to the complex interactions that govern the self-assembly, it is difficult to predict and control the superstructure organization of CCs. Herein, a facile yet effective way is demonstrated to fabricate oriented CCs from capillary assembly of polymer-tethered gold NPs (AuNPs). Assembly mechanism of polymer-tethered AuNPs and their superlattice structures are systematically studied by in situ small-angle X-ray scattering (SAXS) technology. The results show that the oriented CCs of polymer-tethered AuNPs can be obtained upon solvent evaporation in a capillary tube and the oriented structure is mainly determined by the chain length of polymer ligands and size of AuNPs. Assembly of AuNPs tethered by short-chain ligand can result in oriented face-centered cubic (fcc) superlattice, whereas AuNPs tethered by long-chain ligand can assemble into an oriented body-centered tetragonal (bct) superlattice structure. Interestingly, in situ SAXS study shows that for the sample of bct superlattice structure, a transformation from fcc to bct superlattice upon solvent evaporation is observed, which strongly depends on chain length of ligands. This work provides a useful guide for polymer-tethered AuNPs to prepare orientation colloidal crystals.
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Affiliation(s)
- Yutong Gao
- Key Laboratory of Materials Chemistry for Energy Conversion and Storage (HUST) of Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology (HUST), Wuhan, 430074, China
| | - Youshuang Zhou
- Key Laboratory for the Green Preparation and Application of Functional Materials of Ministry of Education, Hubei Key Laboratory of Polymer Materials, Faculty of Materials Science and Engineering, Hubei University, Wuhan, 430062, China
| | - Xiangyun Xu
- Key Laboratory of Materials Chemistry for Energy Conversion and Storage (HUST) of Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology (HUST), Wuhan, 430074, China
| | - Chungui Chen
- Key Laboratory of Materials Chemistry for Energy Conversion and Storage (HUST) of Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology (HUST), Wuhan, 430074, China
| | - Bijin Xiong
- Key Laboratory of Materials Chemistry for Energy Conversion and Storage (HUST) of Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology (HUST), Wuhan, 430074, China
| | - Jintao Zhu
- Key Laboratory of Materials Chemistry for Energy Conversion and Storage (HUST) of Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology (HUST), Wuhan, 430074, China
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Choi BB, Kim B, Chen Y, Yoo SJ, Cho Y, Jiang P. Elevated surface plasmon resonance sensing sensitivity of Au-covered silica sphere monolayer prepared by Langmuir–Blodgett coating. J IND ENG CHEM 2021. [DOI: 10.1016/j.jiec.2021.04.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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7
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Cai Z, Li Z, Ravaine S, He M, Song Y, Yin Y, Zheng H, Teng J, Zhang A. From colloidal particles to photonic crystals: advances in self-assembly and their emerging applications. Chem Soc Rev 2021; 50:5898-5951. [PMID: 34027954 DOI: 10.1039/d0cs00706d] [Citation(s) in RCA: 136] [Impact Index Per Article: 45.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Over the last three decades, photonic crystals (PhCs) have attracted intense interests thanks to their broad potential applications in optics and photonics. Generally, these structures can be fabricated via either "top-down" lithographic or "bottom-up" self-assembly approaches. The self-assembly approaches have attracted particular attention due to their low cost, simple fabrication processes, relative convenience of scaling up, and the ease of creating complex structures with nanometer precision. The self-assembled colloidal crystals (CCs), which are good candidates for PhCs, have offered unprecedented opportunities for photonics, optics, optoelectronics, sensing, energy harvesting, environmental remediation, pigments, and many other applications. The creation of high-quality CCs and their mass fabrication over large areas are the critical limiting factors for real-world applications. This paper reviews the state-of-the-art techniques in the self-assembly of colloidal particles for the fabrication of large-area high-quality CCs and CCs with unique symmetries. The first part of this review summarizes the types of defects commonly encountered in the fabrication process and their effects on the optical properties of the resultant CCs. Next, the mechanisms of the formation of cracks/defects are discussed, and a range of versatile fabrication methods to create large-area crack/defect-free two-dimensional and three-dimensional CCs are described. Meanwhile, we also shed light on both the advantages and limitations of these advanced approaches developed to fabricate high-quality CCs. The self-assembly routes and achievements in the fabrication of CCs with the ability to open a complete photonic bandgap, such as cubic diamond and pyrochlore structure CCs, are discussed as well. Then emerging applications of large-area high-quality CCs and unique photonic structures enabled by the advanced self-assembly methods are illustrated. At the end of this review, we outlook the future approaches in the fabrication of perfect CCs and highlight their novel real-world applications.
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Affiliation(s)
- Zhongyu Cai
- Research Institute for Frontier Science, Beijing Advanced Innovation Center for Biomedical Engineering, School of Space and Environment, Beihang University, Beijing 100191, China. and Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, 117576, Singapore and Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Zhiwei Li
- Department of Chemistry, University of California, Riverside, CA 92521, USA
| | - Serge Ravaine
- CNRS, Univ. Bordeaux, CRPP, UMR 5031, F-33600 Pessac, France
| | - Mingxin He
- Department of Physics, Center for Soft Matter Research, New York University, New York, NY 10003, USA
| | - Yanlin Song
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Yadong Yin
- Department of Chemistry, University of California, Riverside, CA 92521, USA
| | - Hanbin Zheng
- CNRS, Univ. Bordeaux, CRPP, UMR 5031, F-33600 Pessac, France
| | - Jinghua Teng
- Institute of Materials Research and Engineering, Agency for Science, Technology, and Research (A*STAR), 2 Fusionopolis Way, Innovis, #08-03, Singapore 138634, Singapore.
| | - Ao Zhang
- Research Institute for Frontier Science, Beijing Advanced Innovation Center for Biomedical Engineering, School of Space and Environment, Beihang University, Beijing 100191, China.
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Gimenez AV, Kho KW, Keyes TE. Nano-substructured plasmonic pore arrays: a robust, low cost route to reproducible hierarchical structures extended across macroscopic dimensions. NANOSCALE ADVANCES 2020; 2:4740-4756. [PMID: 36132883 PMCID: PMC9417107 DOI: 10.1039/d0na00527d] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 08/11/2020] [Indexed: 05/17/2023]
Abstract
Plasmonic nanostructures are important across diverse applications from sensing to renewable energy. Periodic porous array structures are particularly attractive because such topography offers a means to encapsulate or capture solution phase species and combines both propagating and localised plasmonic modes offering versatile addressability. However, in analytical spectroscopic applications, periodic pore arrays have typically reported weaker plasmonic signal enhancement compared to particulate structures. This may be addressed by introducing additional nano-structuring into the array to promote plasmonic coupling that promotes electric field-enhancement, whilst retaining pore structure. Introducing nanoparticle structures into the pores is a useful means to promote such coupling. However, current approaches rely on either expensive top-down methods or on bottom-up methods that yield random particle placement and distribution. This report describes a low cost, top-down technique for preparation of nano-sub-structured plasmonic pore arrays in a highly reproducible manner that can be applied to build arrays extending over macroscopic areas of mm2 to cm2. The method exploits oxygen plasma etching, under controlled conditions, of the cavity encapsulated templating polystyrene (PS) spheres used to create the periodic array. Subsequent metal deposition leads to reproducible nano-structuring within the wells of the pore array, coined in-cavity nanoparticles (icNPs). This approach was demonstrated across periodic arrays with pore/sphere diameters ranging from 500 nm to 3 μm and reliably improved the plasmonic properties of the substrate across all array dimensions compared to analogous periodic arrays without the nano-structuring. The enhancement factors achieved for metal enhanced emission and surface enhanced Raman spectroscopy depended on the substrate dimensions, with the best performance achieved for nanostructured 2 μm diameter pore arrays, where a more than 104 improvement over Surface Enhanced Raman Spectroscopy (SERS) and 200-fold improvement over Metal Enhanced Fluorescence (MEF) were observed for these substrates compared with analogous unmodified pore arrays. The experiments were supported by Finite-Difference Time-Domain (FDTD) calculations used to simulate the electric field distribution as a function of pore nano-structuring.
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Affiliation(s)
- Aurélien V Gimenez
- School of Chemical Sciences & National Centre for Sensor Research, Dublin City University Dublin 9 Ireland
| | - Kiang W Kho
- School of Chemical Sciences & National Centre for Sensor Research, Dublin City University Dublin 9 Ireland
| | - Tia E Keyes
- School of Chemical Sciences & National Centre for Sensor Research, Dublin City University Dublin 9 Ireland
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9
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Bayat F, Tajalli H. Nanosphere lithography: the effect of chemical etching and annealing sequence on the shape and spectrum of nano-metal arrays. Heliyon 2020; 6:e03382. [PMID: 32072062 PMCID: PMC7016265 DOI: 10.1016/j.heliyon.2020.e03382] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 01/12/2020] [Accepted: 02/04/2020] [Indexed: 11/21/2022] Open
Abstract
In this paper, it is shown that the sequence of chemical etching of the template and annealing has a significant effect on the shape and spectrum of the nano-metal arrays fabricated by nanosphere lithography (NSL). Higher nanoparticles with sharp edges are fabricated as a consequence of annealing the metal coated template, which is a 2d colloidal crystal, before chemical etching. Consequently, the absorption spectra of the fabricated sample become much sharper, in comparison with the one that is fabricated with the reversed order and also a shift is observed in the peak wavelength. The achieved result has practical importance for the applications of these nano-metal arrays in localized surface plasmon resonance (LSPR) based sensors.
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Affiliation(s)
- Farzaneh Bayat
- Department of Physics, Azarbaijan Shahid Madani University, Tabriz, Iran
| | - Habib Tajalli
- Photonics Group, Research Institute for Applied Physics and Astronomy, University of Tabriz, Tabriz, Iran
- Biophotonics Research Center, Islamic Azad University of Tabriz, Tabriz, Iran
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10
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Shillingford C, Grebe V, McMullen A, Brujic J, Weck M. Assembly and Dynamic Analysis of Square Colloidal Crystals via Templated Capillary Assembly. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:12205-12214. [PMID: 31497962 DOI: 10.1021/acs.langmuir.9b02124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Capillary assembly has the ability to engineer centimeter-sized regions of discrete colloidal superstructures and microarrays. However, its use as a tool for directing crystallization of colloids into surface-bound nonclose-packed arrays is limited. Furthermore, the use of quantitative particle tracking tools to investigate evaporative assembly dynamics is rarely employed. In this contribution, we use templated capillary assembly to fabricate square-packed lattices of spherical, organosilica colloids using designed patterned boundaries. Particle tracking algorithms reveal that the assembly of square-packed regions is controlled by the interplay between confinement-driven nuclei formation and osmotic pressure-driven restructuring. We find that the incorporation of a square template increases the yield of particles bearing four nearest neighbors (Zn = 4) from 4 to 39%, obtained using a heavier and more viscous solvent. Maximal square-packed domains occur at specific initial particle concentrations (1.75-2.25 wt % or φ = 0.013-0.017), indicating that rearrangements are a function of osmotic force. We use particle tracking methods to dynamically monitor conversions between square and hexagonal packing, revealing a cyclical transition between 4 and 6 coordinated particles throughout meniscus recession. Our method is highly scalable and inexpensive and can be adapted for use with different particle sizes and compositions, as well as for targeted open-packed geometries. Our findings will inform the large area, defect-free assembly of nonclose-packed lattices of unexplored varieties that are necessary for the continued expansion of colloid-based materials with vast applications in optical electronics.
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Liu Z, Tang P, Liu X, Yi Z, Liu G, Wang Y, Liu M. Truncated titanium/semiconductor cones for wide-band solar absorbers. NANOTECHNOLOGY 2019; 30:305203. [PMID: 30884474 DOI: 10.1088/1361-6528/ab109d] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A truncated Ti and Si cones metasurface has been proposed for wide-band solar absorber (WSA), which produced a high average absorption of 94.7% in the spectral region from 500 to 4000 nm. A maximal enhancement factor of 166.0% was achieved by the WSA in comparison with the absorption of Ti/Si cylinder resonators based absorber. Under the standard solar radiance, a high full-spectrum solar absorption efficiency of 96.1% was obtained for the WSA in the energy range from 0.28 to 4.0 eV. The spectral bandwidth with absorption above 90% is up to 3.402 μm, which shows an enhancement factor of 165.0% than that of the WSA intercalated by the SiO2. Other semiconductors such as Ge, GaAs have been utilized to form the WSA, which also maintained the near-unity absorption in the wide-band spectrum. The plasmonic resonant response of the Ti material and the strong electromagnetic coupling capability of the Si resonator, and the plasmonic near-field coupling by the adjacent truncated cones were the main contributions for the impressive absorption behaviors. These findings pave a new way for achieving full-spectrum solar absorber via combining the Ti material and semiconductors, which could open potential approaches for active optoelectronic devices such as photo-detectors, hot-electron related modulators, and solar cells, etc.
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Affiliation(s)
- Zhengqi Liu
- Jiangxi Key Laboratory of Nanomaterials and Sensors, Provincial Key Laboratory of Optoelectronic and Telecommunication, College of Physics Communication and Electronics, Jiangxi Normal University, Nanchang 330022, People's Republic of China
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Raza S, Lavieja C, Zhu X, Kristensen A. Resonant laser printing of bi-material metasurfaces: from plasmonic to photonic optical response. OPTICS EXPRESS 2018; 26:20203-20210. [PMID: 30119334 DOI: 10.1364/oe.26.020203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 06/22/2018] [Indexed: 06/08/2023]
Abstract
Metasurfaces are nanostructured surfaces with engineered optical properties - currently impacting many branches of optics, from miniaturization of optical components to realizing high-resolution structural colors. The optical properties of metasurfaces can be traced to the individual meta-atoms, which set the nature of the optical response, e.g., plasmonic for metallic meta-atoms or photonic for dielectric meta-atoms. Combining multiple types of responses opens up new horizons in design of optical materials, but has so far been avoided due to the fabrication difficulties associated with constructing a metasurface composed of several meta-atom materials. Here, we present a multi-material design approach by optically post-processing a metasurface constructed from self-assembled polystyrene spheres coated with silver. Using our concept of resonant laser printing, we locally alter the initial plasmonic response of the meta-atoms to a pure photonic response. Our work constitutes a conceptually different way of designing metasurfaces and can pave the way for realizing multi-material metasurfaces on large areas while being cost effective.
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13
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Piccolo V, Chiappini A, Armellini C, Barozzi M, Lukowiak A, Sazio PJA, Vaccari A, Ferrari M, Zonta D. 2D Optical Gratings Based on Hexagonal Voids on Transparent Elastomeric Substrate. MICROMACHINES 2018; 9:E345. [PMID: 30424278 PMCID: PMC6082248 DOI: 10.3390/mi9070345] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 07/06/2018] [Accepted: 07/09/2018] [Indexed: 11/16/2022]
Abstract
A chromatic vectorial strain sensor constituted by hexagonal voids on transparent elastomeric substrate has been successfully fabricated via soft colloidal lithography. Initially a highly ordered 1.6 microns polystyrene spheres monolayer colloidal crystal has been realized by wedge-shaped cell method and used as a suitable mold to replicate the periodic structure on a polydimethylsiloxane sheet. The replicated 2D array is characterized by high periodicity and regularity over a large area, as evidenced by morphological and optical properties obtained by means of SEM, absorption and reflectance spectroscopy. In particular, the optical features of the nanostructured elastomer have been investigated in respect to uniaxial deformation up to 10% of its initial length, demonstrating a linear, tunable and reversible response, with a sensitivity of 4.5 ± 0.1 nm/%. Finally, it has been demonstrated that the specific geometrical configuration allows determining simultaneously the vectorial strain-stress information in the x and y directions.
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Affiliation(s)
| | - Andrea Chiappini
- IFN-CNR CSMFO Lab & FBK CMM, Via alla Cascata 56/C, 38123 Trento, Italy.
| | - Cristina Armellini
- IFN-CNR CSMFO Lab & FBK CMM, Via alla Cascata 56/C, 38123 Trento, Italy.
| | - Mario Barozzi
- CMM-MNF, Fondazione Bruno Kessler, Via Sommarive 18, 38123 Trento (Povo), Italy.
| | - Anna Lukowiak
- Institute of Low Temperature and Structure Research PAS, 50-422 Wroclaw, Poland.
| | - Pier-John A Sazio
- ORC, University of Southampton, University Road, Southampton SO17 1BJ, UK.
| | - Alessandro Vaccari
- CMM-ARES, Fondazione Bruno Kessler, Via Sommarive 18, 38123 Trento (Povo), Italy.
| | - Maurizio Ferrari
- IFN-CNR CSMFO Lab & FBK CMM, Via alla Cascata 56/C, 38123 Trento, Italy.
- Enrico Fermi Centre, Piazza del Viminale 1, 00184 Roma, Italy.
| | - Daniele Zonta
- IFN-CNR CSMFO Lab & FBK CMM, Via alla Cascata 56/C, 38123 Trento, Italy.
- Department of Civil and Environmental Engineering, University of Strathclyde, Montrose Street, 75, Glasgow G1 1XJ, UK.
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14
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Kumar P, Oh SY, Baliyan VK, Kundu S, Lee SH, Kang SW. Topographically induced homeotropic alignment of liquid crystals on self-assembled opal crystals. OPTICS EXPRESS 2018; 26:8385-8396. [PMID: 29715806 DOI: 10.1364/oe.26.008385] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 03/13/2018] [Indexed: 06/08/2023]
Abstract
The surface of multilayered opal crystals resulted in homeotropic alignment of liquid crystal (LC), originated from the surface topography of opal crystals rather than a chemical nature of the nanoparticles. The polar anchoring energy (5.51 × 10-5 J/m2) of the crystal surface for nematic LC molecules was in a similar range to the conventional polyimide alignment layer (2.11 × 10-5 J/m2) used for commercial applications. The critical length scale for anchoring transition was approximately Lw = ~1 μm. If a diameter of particle d << 1 μm for opal crystals, LC molecules preferred to anchor vertically to the surface to minimize elastic free energy of bulk LCs. The LC favored a planar anchoring if d >> 1 μm. The results provide crucial insights to understand the homeotropic alignment of LCs on solid surfaces and therefore offer opportunities to develop novel materials for a vertical alignment of LCs.
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15
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García Núñez C, Navaraj WT, Liu F, Shakthivel D, Dahiya R. Large-Area Self-Assembly of Silica Microspheres/Nanospheres by Temperature-Assisted Dip-Coating. ACS APPLIED MATERIALS & INTERFACES 2018; 10:3058-3068. [PMID: 29280379 DOI: 10.1021/acsami.7b15178] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
This work reports a temperature-assisted dip-coating method for self-assembly of silica (SiO2) microspheres/nanospheres (SPs) as monolayers over large areas (∼cm2). The area over which self-assembled monolayers (SAMs) are formed can be controlled by tuning the suspension temperature (Ts), which allows precise control over the meniscus shape. Furthermore, the formation of periodic stripes of SAMs, with excellent dimensional control (stripe width and stripe-to-stripe spacing), is demonstrated using a suitable set of dip-coating parameters. These findings establish the role of Ts, and other parameters such as withdrawal speed (Vw), withdrawal angle (θw), and withdrawal step length (Lw). For Ts ranged between 25 and 80 °C, the morphological analysis of dip-coatings shows layered structures comprising of defective layers (25-60 °C), single layers (70 °C), and multilayers (>70 °C) owing to the variation of SP flux at the meniscus/substrate assembling interface. At Ts = 70 °C, there is an optimum Vw, approximately equal to the downshift speed of the meniscus (Vm = 1.3 μm/s), which allows the SAM formation over areas (2.25 cm2) roughly 10 times larger than reported in the literature using nanospheres. Finally, the large-area SAM is used to demonstrate the enhanced performance of antireflective coatings for photovoltaic cells and to create metal nanomesh for Si nanowire synthesis.
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Affiliation(s)
- Carlos García Núñez
- School of Engineering, University of Glasgow, Bendable Electronics and Sensing Technologies , G12 8QQ Glasgow, U.K
| | - William Taube Navaraj
- School of Engineering, University of Glasgow, Bendable Electronics and Sensing Technologies , G12 8QQ Glasgow, U.K
| | - Fengyuan Liu
- School of Engineering, University of Glasgow, Bendable Electronics and Sensing Technologies , G12 8QQ Glasgow, U.K
| | - Dhayalan Shakthivel
- School of Engineering, University of Glasgow, Bendable Electronics and Sensing Technologies , G12 8QQ Glasgow, U.K
| | - Ravinder Dahiya
- School of Engineering, University of Glasgow, Bendable Electronics and Sensing Technologies , G12 8QQ Glasgow, U.K
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16
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Coll A, Bermejo S, Hernández D, Castañer L. Al 2O 3/TiO 2 inverse opals from electrosprayed self-assembled templates. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2018; 9:216-223. [PMID: 29441266 PMCID: PMC5789432 DOI: 10.3762/bjnano.9.23] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 12/21/2017] [Indexed: 06/08/2023]
Abstract
The fabrication of high optical quality inverse opals is challenging, requiring large size, three-dimensional ordered layers of high dielectric constant ratio. In this article, alumina/TiO2-air inverse opals with a 98.2% reflectivity peak at 798 nm having an area of 2 cm2 and a thickness of 17 µm are achieved using a sacrificial self-assembled structure of large thickness, which was produced with minimum fabrication errors by means of an electrospray technique. Using alumina as the first supporting layer enables the deposition of TiO2 at a higher temperature, therefore providing better optical quality.
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Affiliation(s)
- Arnau Coll
- Research Group in Micro and Nano Technologies, Electronic Engineering Department, Universitat Politècnica de Catalunya, Jordi Girona 1-3, 08034 Barcelona, Spain
| | - Sandra Bermejo
- Research Group in Micro and Nano Technologies, Electronic Engineering Department, Universitat Politècnica de Catalunya, Jordi Girona 1-3, 08034 Barcelona, Spain
| | - David Hernández
- Research Group in Micro and Nano Technologies, Electronic Engineering Department, Universitat Politècnica de Catalunya, Jordi Girona 1-3, 08034 Barcelona, Spain
| | - Luís Castañer
- Research Group in Micro and Nano Technologies, Electronic Engineering Department, Universitat Politècnica de Catalunya, Jordi Girona 1-3, 08034 Barcelona, Spain
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17
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Ultra-broadband Tunable Resonant Light Trapping in a Two-dimensional Randomly Microstructured Plasmonic-photonic Absorber. Sci Rep 2017; 7:43803. [PMID: 28256599 PMCID: PMC5335598 DOI: 10.1038/srep43803] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 01/30/2017] [Indexed: 11/08/2022] Open
Abstract
Recently, techniques involving random patterns have made it possible to control the light trapping of microstructures over broad spectral and angular ranges, which provides a powerful approach for photon management in energy efficiency technologies. Here, we demonstrate a simple method to create a wideband near-unity light absorber by introducing a dense and random pattern of metal-capped monodispersed dielectric microspheres onto an opaque metal film; the absorber works due to the excitation of multiple optical and plasmonic resonant modes. To further expand the absorption bandwidth, two different-sized metal-capped dielectric microspheres were integrated into a densely packed monolayer on a metal back-reflector. This proposed ultra-broadband plasmonic-photonic super absorber demonstrates desirable optical trapping in dielectric region and slight dispersion over a large incident angle range. Without any effort to strictly control the spatial arrangement of the resonant elements, our absorber, which is based on a simple self-assembly process, has the critical merits of high reproducibility and scalability and represents a viable strategy for efficient energy technologies.
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18
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Hiraiwa M, Abi Ghanem M, Wallen SP, Khanolkar A, Maznev AA, Boechler N. Complex Contact-Based Dynamics of Microsphere Monolayers Revealed by Resonant Attenuation of Surface Acoustic Waves. PHYSICAL REVIEW LETTERS 2016; 116:198001. [PMID: 27232047 DOI: 10.1103/physrevlett.116.198001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Indexed: 05/09/2023]
Abstract
Contact-based vibrations play an essential role in the dynamics of granular materials. Significant insights into vibrational granular dynamics have previously been obtained with reduced-dimensional systems containing macroscale particles. We study contact-based vibrations of a two-dimensional monolayer of micron-sized spheres on a solid substrate that forms a microscale granular crystal. Measurements of the resonant attenuation of laser-generated surface acoustic waves reveal three collective vibrational modes that involve displacements and rotations of the microspheres, as well as interparticle and particle-substrate interactions. To identify the modes, we tune the interparticle stiffness, which shifts the frequency of the horizontal-rotational resonances while leaving the vertical resonance unaffected. From the measured contact resonance frequencies we determine both particle-substrate and interparticle contact stiffnesses and find that the former is an order of magnitude larger than the latter. This study paves the way for investigating complex contact-based dynamics of microscale granular crystals and yields a new approach to studying micro- to nanoscale contact mechanics in multiparticle networks.
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Affiliation(s)
- M Hiraiwa
- Department of Mechanical Engineering, University of Washington, Seattle, Washington 98195, USA
| | - M Abi Ghanem
- Department of Mechanical Engineering, University of Washington, Seattle, Washington 98195, USA
| | - S P Wallen
- Department of Mechanical Engineering, University of Washington, Seattle, Washington 98195, USA
| | - A Khanolkar
- Department of Mechanical Engineering, University of Washington, Seattle, Washington 98195, USA
| | - A A Maznev
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - N Boechler
- Department of Mechanical Engineering, University of Washington, Seattle, Washington 98195, USA
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19
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Shinotsuka K, Kajita Y, Hongo K, Hatta Y. Crystal Perfection of Particle Monolayer at the Air-Water Interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:11452-11457. [PMID: 26434777 DOI: 10.1021/acs.langmuir.5b03151] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Crystal growth in colloidal particle monolayers fabricated by Langmuir-Blodgett method on 4 in. sapphire wafers was investigated under the condition of two techniques, that is, ultrasonic annealing at 1.2 to 1.5 MHz and barrier-sway process at 0.2 to 0.5 Hz. Significant increases of the ordered area were obtained by the both techniques and more than 60 times growth was confirmed. The remaining crystal defects after the growth were categorized as grain boundary, vacancy, and line defect. Both techniques exhibited different features regarding the component ratio of the defects, and different mechanisms for the reorientation of particles are discussed. The driving force of these re-orientations is thought to be associated with the 2D Ostwald ripening of colloidal crystals.
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Affiliation(s)
- Kei Shinotsuka
- Development Center, Innovation Promotion Division, Oji Holdings Corporation , 1-10-6, Shinonome, Koto-ku, Tokyo 135-8558, Japan
| | - Yasuhito Kajita
- Development Center, Innovation Promotion Division, Oji Holdings Corporation , 1-10-6, Shinonome, Koto-ku, Tokyo 135-8558, Japan
| | - Koki Hongo
- Development Center, Innovation Promotion Division, Oji Holdings Corporation , 1-10-6, Shinonome, Koto-ku, Tokyo 135-8558, Japan
| | - Yoshihisa Hatta
- Development Center, Innovation Promotion Division, Oji Holdings Corporation , 1-10-6, Shinonome, Koto-ku, Tokyo 135-8558, Japan
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20
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Shi L, Yuan X, Zhang Y, Hakala T, Yin S, Han D, Zhu X, Zhang B, Liu X, Törmä P, Lu W, Zi J. Coherent fluorescence emission by using hybrid photonic-plasmonic crystals. LASER & PHOTONICS REVIEWS 2014; 8:717-725. [PMID: 25793015 PMCID: PMC4358154 DOI: 10.1002/lpor.201300196] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 05/26/2014] [Accepted: 05/26/2014] [Indexed: 05/21/2023]
Abstract
The spatial and temporal coherence of the fluorescence emission controlled by a quasi-two-dimensional hybrid photonic-plasmonic crystal structure covered with a thin fluorescent-molecular-doped dielectric film is investigated experimentally. A simple theoretical model to describe how a confined quasi-two-dimensional optical mode may induce coherent fluorescence emission is also presented. Concerning the spatial coherence, it is experimentally observed that the coherence area in the plane of the light source is in excess of 49 μm2, which results in enhanced directional fluorescence emission. Concerning temporal coherence, the obtained coherence time is 4 times longer than that of the normal fluorescence emission in vacuum. Moreover, a Young's double-slit interference experiment is performed to directly confirm the spatially coherent emission. This smoking gun proof of spatial coherence is reported here for the first time for the optical-mode-modified emission.
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Affiliation(s)
- Lei Shi
- Department of Physics, Key Laboratory of Micro & Nano Photonic Structures (MOE) and Key Laboratory of Surface Physics, Fudan UniversityShanghai 200433, P. R. China
- COMP Centre of Excellence, Department of Applied Physics, Aalto UniversityFI-00076 Aalto, Finland
- *Corresponding author: e-mail: , , , ,
| | - Xiaowen Yuan
- National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences200083 Shanghai, China
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology430074 Wuhan, China
| | - Yafeng Zhang
- Department of Physics, Key Laboratory of Micro & Nano Photonic Structures (MOE) and Key Laboratory of Surface Physics, Fudan UniversityShanghai 200433, P. R. China
| | - Tommi Hakala
- COMP Centre of Excellence, Department of Applied Physics, Aalto UniversityFI-00076 Aalto, Finland
| | - Shaoyu Yin
- COMP Centre of Excellence, Department of Applied Physics, Aalto UniversityFI-00076 Aalto, Finland
| | - Dezhuan Han
- Department of Physics, Key Laboratory of Micro & Nano Photonic Structures (MOE) and Key Laboratory of Surface Physics, Fudan UniversityShanghai 200433, P. R. China
| | - Xiaolong Zhu
- Department of Physics, Key Laboratory of Micro & Nano Photonic Structures (MOE) and Key Laboratory of Surface Physics, Fudan UniversityShanghai 200433, P. R. China
| | - Bo Zhang
- National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences200083 Shanghai, China
- *Corresponding author: e-mail: , , , ,
| | - Xiaohan Liu
- Department of Physics, Key Laboratory of Micro & Nano Photonic Structures (MOE) and Key Laboratory of Surface Physics, Fudan UniversityShanghai 200433, P. R. China
- *Corresponding author: e-mail: , , , ,
| | - Päivi Törmä
- COMP Centre of Excellence, Department of Applied Physics, Aalto UniversityFI-00076 Aalto, Finland
| | - Wei Lu
- National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences200083 Shanghai, China
- *Corresponding author: e-mail: , , , ,
| | - Jian Zi
- Department of Physics, Key Laboratory of Micro & Nano Photonic Structures (MOE) and Key Laboratory of Surface Physics, Fudan UniversityShanghai 200433, P. R. China
- *Corresponding author: e-mail: , , , ,
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21
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May K, Stannarius R, Klein S, Eremin A. Electric-field-induced phase separation and homogenization dynamics in colloidal suspensions of dichroic rod-shaped pigment particles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:7070-7076. [PMID: 24866927 DOI: 10.1021/la501120k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We report a reversible phase separation phenomenon in nonpolar colloidal suspensions of rod-shaped dichroic pigment particles in an electric field. The voltage-frequency phase diagram features a variety of phases with different morphologies. Single static particle-rich islands, chains of islands, and dynamic patterns were found in this system. We demonstrate that those patterns exhibit complex relaxation dynamics toward the homogeneous field-free state once the external field is removed.
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Affiliation(s)
- Kathrin May
- Otto von Guericke University , Institute for Experimental Physics, Department for Nonlinear Phenomena, 39106 Magdeburg, Germany
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22
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Meng X, Zhang X, Ye L, Qiu D. Fabrication of large-sized two-dimensional ordered surface array with well-controlled structure via colloidal particle lithography. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:7024-7029. [PMID: 24870696 DOI: 10.1021/la501033f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Epoxy resin coated glass slides were used for colloidal particle lithography, in order to prepare well-defined 2D surface arrays. Upon the assistance of a large-sized 2D colloidal single crystal as template, centimeter-sized ordered surface arrays of bowl-like units were obtained. Systematic studies revealed that the parameters of obtained surface arrays could be readily controlled by some operational factors, such as temperature, epoxy resin layer thickness, and template particle size. With epoxy resin substituting for normal linear polymer, the height/diameter ratio of bowls in the formed surface arrays can be largely increased. With further reactive plasma etching, the parameters of ordered surface arrays could be finely tuned through controlling etching time. This study provides a facile way to prepare large-sized 2D surface arrays with tunable parameters.
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Affiliation(s)
- Xiaohui Meng
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China
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23
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Lu H, Tang C, Du W, Liu F, Xing Y, Zhan P, Chen Z, Wang Z. Optical transmission of planar metallic films coated by two-dimensional colloidal crystals. OPTICS EXPRESS 2014; 22:11698-11706. [PMID: 24921292 DOI: 10.1364/oe.22.011698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Optical transmissions through a continuous planar metal film (without holes) with two-dimensional colloidal crystals coated on one or both interfaces have been experimentally and numerically investigated. Enhanced optical transmissions in the near-infrared regime can be observed for the metal film with identical two-dimensional colloidal crystals coated on both sides, which occur due to the resonant tunneling of surface polariton Bloch eigenmodes excited on periodically structured interfaces. Numerical simulations of transmission spectra show an excellent agreement with the measured ones. Additionally, the numerical simulations reveal that the intensity of tunneling transmission is strongly dependent on the relative shift of the two-dimensional colloidal crystals on the opposite interfaces of the metallic film.
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24
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Zhu X, Wang W, Yan W, Larsen MB, Bøggild P, Pedersen TG, Xiao S, Zi J, Mortensen NA. Plasmon-phonon coupling in large-area graphene dot and antidot arrays fabricated by nanosphere lithography. NANO LETTERS 2014; 14:2907-2913. [PMID: 24707792 DOI: 10.1021/nl500948p] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Nanostructured graphene on SiO2 substrates paves the way for enhanced light-matter interactions and explorations of strong plasmon-phonon hybridization in the mid-infrared regime. Unprecedented large-area graphene nanodot and antidot optical arrays are fabricated by nanosphere lithography, with structural control down to the sub-100 nm regime. The interaction between graphene plasmon modes and the substrate phonons is experimentally demonstrated, and structural control is used to map out the hybridization of plasmons and phonons, showing coupling energies of the order 20 meV. Our findings are further supported by theoretical calculations and numerical simulations.
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Affiliation(s)
- Xiaolong Zhu
- Department of Photonics Engineering, Technical University of Denmark , DK-2800 Kongens Lyngby, Denmark
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25
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Meng X, Qiu D. Gas-flow-induced reorientation to centimeter-sized two-dimensional colloidal single crystal of polystyrene particle. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:3019-3023. [PMID: 24588268 DOI: 10.1021/la404944w] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Centimeter-sized two-dimensional (2D) colloidal single crystals of polystyrene (PS) particles were fabricated at the water/air interface by capillary-modulated self-assembly. Different from previous reports, in this work, emulsifier was used to facilitate the stress release during 2D colloidal crystal formation by adjusting the interparticle lateral interactions. With the assistance of compressed nitrogen flow, 2D hexagonal colloidal single crystals of centimeter size were obtained under appropriate emulsifier concentrations. A new method was also developed to transfer the 2D colloidal crystals from the air/water interface to the desired substrate without obvious disturbance. This new transferring method was proven not to be sensitive to surface wettability nor curvature, thus 2D colloidal single crystals with large areas could be obtained on different kinds of substrate.
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Affiliation(s)
- Xiaohui Meng
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China
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26
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Recent advances in fabrication of monolayer colloidal crystals and their inverse replicas. Sci China Chem 2013. [DOI: 10.1007/s11426-013-5018-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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27
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Rong JH, Ji LJ, Yang ZZ. Some key ordered macroporous composites. CHINESE JOURNAL OF POLYMER SCIENCE 2013. [DOI: 10.1007/s10118-013-1324-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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28
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Boechler N, Eliason JK, Kumar A, Maznev AA, Nelson KA, Fang N. Interaction of a contact resonance of microspheres with surface acoustic waves. PHYSICAL REVIEW LETTERS 2013; 111:036103. [PMID: 23909341 DOI: 10.1103/physrevlett.111.036103] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 06/11/2013] [Indexed: 06/02/2023]
Abstract
We study the interaction of surface acoustic waves (SAWs) with a contact-based vibrational resonance of 1 μm silica microspheres forming a two-dimensional granular crystal adhered to a substrate. The laser-induced transient grating technique is used to excite SAWs and measure their dispersion. The measured dispersion curves exhibit "avoided crossing" behavior due to the hybridization of the SAWs with the microsphere resonance. We compare the measured dispersion curves with those predicted by our analytical model and find excellent agreement. The approach presented can be used to study the contact mechanics and adhesion of micro- and nanoparticles as well as the dynamics of microscale granular crystals.
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Affiliation(s)
- N Boechler
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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29
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Sun X, Li Y, Zhang TH, Ma YQ, Zhang Z. Fabrication of large two-dimensional colloidal crystals via self-assembly in an attractive force gradient. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:7216-7220. [PMID: 23311289 DOI: 10.1021/la304720h] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Colloidal particles in a water-lutidine (WL) binary liquid mixture experience temperature-dependent attraction close to the mixture's demixing temperature. This temperature-tunable interaction can be potentially harnessed to assemble colloids and grow colloidal crystals. In this article, for the first time a novel attractive force gradient method is presented to fabricate high-quality, single-domain colloidal crystals. The well-controlled attractive force gradient here arises from a temperature gradient in the WL mixture. The nucleation of colloidal crystals in such a WL mixture preferably occurs in the high-temperature region because of the stronger attraction there. Crystallization propagates from the high-temperature region to the low-temperature region in a well-controlled way. The growth of the colloidal crystal is characterized in detail by Voronoi construction, the pair correlation function, and the orientational order parameter. It is found that the number of crystal-like particles increases with time, and a single-domain 2D colloidal crystal can be produced. The mechanism of the defect-free crystallization process is discussed on the basis of an analogy to cluster beam deposition methods. This study demonstrates an efficient and robust way to prepare colloidal crystals with little to no defects, being suitable for applications such as colloidal lithography and the fabrication of perfect 3D colloidal crystals.
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Affiliation(s)
- Xiaoyan Sun
- Center for Soft Condensed Matter Physics and Interdisciplinary Research, Soochow University, Suzhou 215006, PR China
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30
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Chen H, Lv T, Zheng A, Han Y. Controlled switching of discrete solitons in periodically poled lithium niobate waveguide arrays. APPLIED OPTICS 2013; 52:1663-1667. [PMID: 23478770 DOI: 10.1364/ao.52.001663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 02/07/2013] [Indexed: 06/01/2023]
Abstract
We suggest an effective method for controlling nonlinear switching in one-dimensional waveguide arrays formed by the periodically poled lithium niobate. We demonstrate that the ability of switching for discrete solitons is relative to the coupling coefficient that is determined by the applied external electrical field on periodically poled lithium niobate waveguide arrays. Besides the external electrical field, the switching of the discrete solitons is also determined by the excited beams tilted angle. It provides us an easy way to control the light beam propagation in such waveguide arrays based on electro-optical effects when an external electric field is applied.
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Affiliation(s)
- Hongyun Chen
- School of Mathematics and Physics, China University of Geosciences, Wuhan, China.
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31
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Ye R, Ye YH, Zhou Z, Xu H. Gravity-assisted convective assembly of centimeter-sized uniform two-dimensional colloidal crystals. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:1796-1801. [PMID: 23327559 DOI: 10.1021/la3040227] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We have developed an inexpensive, robust, and easily controlled method, a gravity-assisted convective self-assembly method, to fabricate centimeter-sized uniform two-dimensional colloidal crystals. In this method, centimeter-sized two-dimensional colloidal crystals can be formed when the suspension concentration is in the range of 0.32-2.5 wt %. Once the ordering process starts, the formation of two-dimensional colloidal crystals is not affected when the environmental temperature gradually increases from 3 to 10 °C. Experimental results indicate that, in this method, gravity plays an important role in the colloidal crystal formation. The colloidal particles are transported to the edge of the suspension-glass interface, and the extra particles can be eventually moved to the edge of the slide by gravity.
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Affiliation(s)
- Ran Ye
- Department of Physics, Nanjing Normal University, Nanjing 210097, China
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32
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Wang J, Yang L, Lin D, Luo Y, Li D, Meng Q. Optical studies of random disorder of colloidal photonic crystals and its evolution in evaporation induced self-assembly. J Chem Phys 2012; 137:234111. [DOI: 10.1063/1.4772095] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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33
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Chen J, Shen Q, Chen Z, Wang Q, Tang C, Wang Z. Multiple Fano resonances in monolayer hexagonal non-close-packed metallic shells. J Chem Phys 2012; 136:214703. [PMID: 22697562 DOI: 10.1063/1.4725539] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In this study, we first numerically investigate the appearance and properties of multiple Fano resonances in two-dimensional hexagonal non-close-packed arrays of symmetric metallic shells. The coexistence of broad sphere-like plasmon modes formed from the near-field interaction between the individual sphere plasmons and substantially narrower void plasmon modes supported by the inner surface of the individual shell resonant over the same range of energies can produce such Fano resonances. In particular, void and sphere-like plasmon modes of different angular momentum could directly interact without the need of symmetry breaking in the structure. A cost-effective colloidal crystal templating method is utilized to prepare the arrays of the metallic shells with small openings. The effect of the symmetry breaking on the Fano resonances in metallic cup arrays is experimentally and numerically investigated. Further tunability on the Fano resonances is gained by changing the size of the inner dielectric core, hence changing the moment of the void plasmon modes and consequently the resonance frequency. By adopting the polymer dielectric core with gain materials, our study may offer realizable experimental opportunities towards subwavelength low threshold plasmonic lasing.
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Affiliation(s)
- Jing Chen
- Department of Physics and National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China
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34
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Espinha A, Ibisate M, Galisteo-López J, Blanco Á, López C. One-step-process composite colloidal monolayers and further processing aiming at porous membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:13172-13180. [PMID: 22866898 DOI: 10.1021/la302395x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Composite materials consisting of a monolayer of polystyrene spheres (diameters of 430 and 520 nm) and porous silica, filling in the interstices, have been fabricated and characterized. The proposed growth method introduces some novelties as far as the fabrication of this kind of monolayers is concerned, as it probes the compatibility of coassembly (in which a silica precursor, tetraethyl orthosilicate (TEOS), is added to the base colloid) with confined growth in a wedge-shaped cell, while profiting from the advantages of both techniques. Using this method, it is possible to fabricate the composite monolayer in a single growth step. A systematic study of the influence of TEOS concentration in the initial colloid was performed in order to improve the quality of the two-dimensional crystals produced. Thus, it was demonstrated that the two methods are compatible. Furthermore, the composites were then subjected to thermal treatment so that the polymer is removed to reveal the inverse structure. After the calcination the membranes still present very good quality and so the proposed approach is effective for the fabrication of porous membranes. A comparison of reflectance spectra, between composite monolayers fabricated using this method and composites achieved by infiltrating polystyrene bare opals with silica chemical vapor deposition, is also established. The procedure presented is expected to establish the route for an easier and quicker fabrication of inverse monolayers of high refractive index materials with applications in light control.
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Affiliation(s)
- André Espinha
- Instituto de Ciencia de Materiales de Madrid, Sor Juana Inés de la Cruz, 3, 28049 Madrid, Spain
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35
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Zhu X, Zhang C, Liu X, Hansen O, Xiao S, Mortensen NA, Zi J. Evaporation of water droplets on "lock-and-key" structures with nanoscale features. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:9201-9205. [PMID: 22662879 DOI: 10.1021/la301867q] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Highly ordered poly(dimethylsiloxane) microbowl arrays (MBAs) and microcap arrays (MCAs) with "lock-and-key" properties are successfully fabricated by self-assembly and electrochemical deposition. The wetting properties and evaporation dynamics of water droplets for both cases have been investigated. For the MBAs case, the wetting radius of the droplets remains unchanged until the portion of the droplet completely dries out at the end of the evaporation process. The pinning state extends for more than 99.5% of the total evaporation time, and the pinning-shrinking transition is essentially prevented whereas in the case of the MCAs the contact radius exhibits distinct stages during evaporation and the contact line retreats significantly in the middle of the evaporation process. We explain the phenomenon by a qualitative energy balance argument based on the different shrinkage types of the nanoscale-folded contact line.
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Affiliation(s)
- Xiaolong Zhu
- Department of Physics, Key Laboratory of Micro- and Nano-Photonic Structures, Ministry of Education, Fudan University, Shanghai 200433, China
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Galisteo-López JF, López-García M, Blanco A, López C. Studying light propagation in self-assembled hybrid photonic-plasmonic crystals by fourier microscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:9174-9179. [PMID: 22468889 DOI: 10.1021/la300448y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Hybrid metallodielectric systems where dielectric components are combined with metals supporting surface plasmons are able to spatially redistribute the electromagnetic field intensity within its volume through hybrid photonic-plasmonic modes. While most of the work done recently in this kind of systems has been focused on the way such redistribution takes place and how light couples to or is emitted from such samples, the way light propagation takes place has not been studied in depth. Here we consider light propagation in hybrid systems fabricated by self-assembly methods measuring their equifrequency surfaces both in reflection and emission configurations. Comparing spectroscopic measurements with equifrequency surfaces provides a deeper insight into the way light propagates in these structures, showing the possibilities they may present for several applications.
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Affiliation(s)
- J F Galisteo-López
- Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC), C/Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain.
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Zhu X, Xie F, Shi L, Liu X, Mortensen NA, Xiao S, Zi J, Choy W. Broadband enhancement of spontaneous emission in a photonic-plasmonic structure. OPTICS LETTERS 2012; 37:2037-2039. [PMID: 22660113 DOI: 10.1364/ol.37.002037] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We demonstrate that a broadband enhancement of spontaneous emission can be achieved within a photonic-plasmonic structure. The structure can strongly modify the spontaneous emission by exciting plasmonic modes. Because of the excited plasmonic modes, an enhancement up to 30 times is observed, leading to a 4 times broader emission spectrum. The reflectance measurement and the finite-difference time-domain simulation are carried out to support these results.
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Affiliation(s)
- Xiaolong Zhu
- Department of Physics, Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), Fudan University, Shanghai 200433, China
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Liu Z, Hang J, Chen J, Yan Z, Tang C, Chen Z, Zhan P. Optical transmission of corrugated metal films on a two-dimensional hetero-colloidal crystal. OPTICS EXPRESS 2012; 20:9215-9225. [PMID: 22513633 DOI: 10.1364/oe.20.009215] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The near infrared transmission of corrugated metal films deposited on hetero-colloidal crystals is investigated. The transmission response of the quasi-three-dimensional (quasi-3D) metal film is modified by controlling the nominal thickness of a dielectric layer pre-deposited on the top surface of the colloidal crystal to form a new hetero-colloidal crystal. An extraordinary optical transmission (EOT) phenomenon could be presented in such metallodielectric (MD) architectures. We have found that the main transmission peak is suppressed as the thickness of the intercalated dielectric layer is increased. We propose that the observed EOT is a result of constructive interference between a localized sphere-like plasmon mode and an index-guided eigen mode mainly confined in the colloidal crystal, which is confirmed by our numerical simulations. Based on the MD microstructures, a distinct plasmon sensitivity response difference is achieved, which indicates potential applications for biochemical sensing.
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Affiliation(s)
- Zhengqi Liu
- Department of Physics and National Laboratory of Solid State Microstructure, Nanjing University, Nanjing 210093, China
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Zhu X, Xiao S, Shi L, Liu X, Zi J, Hansen O, Mortensen NA. A stretch-tunable plasmonic structure with a polarization-dependent response. OPTICS EXPRESS 2012; 20:5237-5242. [PMID: 22418330 DOI: 10.1364/oe.20.005237] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We experimentally demonstrate a stretchable plasmonic structure composed of a monolayer array of gold semishells with dielectric cores on an elastic PDMS substrate. The composite structure is fabricated using simple and inexpensive self-assembly and transfer-printing techniques, and it supports Bragg-type surface plasmon resonances whose frequencies are sensitive to the arrangement of the metallic semishells. Under uniaxial stretching, the lattice symmetry of this plasmonic structure can be reconfigured from hexagonal to monoclinic, leading to resonance frequency shifts from 200 THz to 191 THz for the TM polarization and from 200 THz to 198 THz for the TE polarization with a strain up to 20%, respectively. Compared with previously reported tunable plasmonic structures, the reconfiguration of lattice symmetry offers a promising approach to tune the surface plasmon resonance with a polarization-dependent response at the standard telecommunication band, and such tunable plasmonic structure might be exploited in realizing photonic devices such as sensors, switches and filters.
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Affiliation(s)
- Xiaolong Zhu
- Department of Photonics Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
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Canalejas-Tejero V, Ibisate M, Golmayo D, Blanco A, López C. Qualitative and quantitative analysis of crystallographic defects present in 2D colloidal sphere arrays. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:161-167. [PMID: 22070340 DOI: 10.1021/la203160d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this work, we present a study of the typical spontaneous defects present in self-assembled colloidal monolayers grown from polystyrene and silica microspheres. The quality of two-dimensional crystals from different colloidal suspensions of beads around 1 μm in diameter has been studied qualitatively and quantitatively, evaluated in 2D hexagonal arrays at different scales through Fourier analysis of SEM images and optical characterization. The crystallographic defects are identified to better understand their origin and their effects on the crystal quality, as well as to find the best conditions colloidal suspensions must fulfill to achieve optimal quality samples.
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Affiliation(s)
- Víctor Canalejas-Tejero
- Instituto de Ciencia de Materiales de Madrid ICMM-CSIC and Unidad Asociada CSIC-UVigo, C/Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain
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Fabrication of large scale two-dimensional colloidal crystal of polystyrene particles by an interfacial self-ordering process. J Colloid Interface Sci 2011; 361:429-35. [DOI: 10.1016/j.jcis.2011.06.011] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Revised: 05/21/2011] [Accepted: 06/02/2011] [Indexed: 11/20/2022]
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Chen X, Li P, Tong H, Kako T, Ye J. Nanoarchitectonics of a Au nanoprism array on WO 3 film for synergistic optoelectronic response. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2011; 12:044604. [PMID: 27877412 PMCID: PMC5090490 DOI: 10.1088/1468-6996/12/4/044604] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 07/07/2011] [Accepted: 04/15/2011] [Indexed: 06/03/2023]
Abstract
A layered photoelectrode consisting of a conductive indium tin oxide substrate, a WO3 nanocrystalline film and an array of Au nanoprisms was fabricated via a multistep process. Scanning electron microscopy and atomic force microscopy showed that the Au nanoprisms had a uniform size and shape and formed periodic hexagonal patterns on the WO3 film. The optical absorption of the photoelectrode combined the intrinsic absorption of WO3 and plasmonic absorption of Au. Using this photoelectrode, we investigated the effect of the Au nanoprism array on the optoelectronic conversion performance of the WO3 film. Photoelectrochemical measurement indicated that the array substantially enhanced the photocurrent in the WO3 film. Electrochemical impedance measurements revealed that the Schottky junctions formed between Au and WO3 can facilitate the separation of photogenerated carriers as well as the interfacial carrier transfer. In this study, we demonstrate that covering a semiconductor with plasmonic noble metal nanoparticles can improve its optoelectronic conversion efficiency.
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Affiliation(s)
- Xiaoqing Chen
- International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
- Department of Chemistry, Graduate School of Science, Hokkaido University, Sapporo, Japan
- Photocatalytic Materials Center, National Institute for Materials Scienc (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
| | - Peng Li
- International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
- Department of Chemistry, Graduate School of Science, Hokkaido University, Sapporo, Japan
- Photocatalytic Materials Center, National Institute for Materials Scienc (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
| | - Hua Tong
- International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
- Photocatalytic Materials Center, National Institute for Materials Scienc (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
| | - Tetsuya Kako
- Department of Chemistry, Graduate School of Science, Hokkaido University, Sapporo, Japan
- Photocatalytic Materials Center, National Institute for Materials Scienc (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
| | - Jinhua Ye
- International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
- Department of Chemistry, Graduate School of Science, Hokkaido University, Sapporo, Japan
- Photocatalytic Materials Center, National Institute for Materials Scienc (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
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Zhang Y, Wang J, Huang Y, Song Y, Jiang L. Fabrication of functional colloidal photonic crystals based on well-designed latex particles. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm10977d] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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