1
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Vasileiadis T, Schöttle M, Theis M, Retsch M, Fytas G, Graczykowski B. Elasticity Mapping of Colloidal Glasses Reveals the Interplay between Mesoscopic Order and Granular Mechanics. SMALL METHODS 2024:e2400855. [PMID: 39139008 DOI: 10.1002/smtd.202400855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2024] [Indexed: 08/15/2024]
Abstract
Colloidal glasses (CGs) made of polymer (polymethylmethacrylate) nanoparticles are promising metamaterials for light and sound manipulation, but fabrication imperfections and fragility can limit their functionality and applications. Here, the vibrational mechanical modes of nanoparticles are probed to evaluate the nanomechanical and morphological properties of various CGs architectures. Utilizing the scanning micro-Brillouin light scattering (µ-BLS), the effective elastic constants and nanoparticles' sizes is determined as a function of position in a remote and non-destructive manner. This method is applied to CG mesostructures with different spatial distributions of their particle size and degree of order. These include CGs with single-sized systems, binary mixtures, bilayer structures, continuous gradient structures, and gradient mixtures. The microenvironments govern the local mechanical properties and highlight how the granular mesostructure can be used to develop durable functional polymer colloids. A size effect is revealed on the effective elastic constant, with the smallest particles and ordered assemblies forming robust structures, and classify the various types of mesoscale order in terms of their mechanical stiffness. The work establishes scanning µ-BLS as a tool for mapping elasticity, particle size, and local structure in complex nanostructures.
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Affiliation(s)
- Thomas Vasileiadis
- Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznanskiego 2, Poznan, 61-614, Poland
| | - Marius Schöttle
- Department of Chemistry, Physical Chemistry I, University of Bayreuth, Universitätsstr. 30, 95447, Bayreuth, Germany
| | - Maximilian Theis
- Department of Chemistry, Physical Chemistry I, University of Bayreuth, Universitätsstr. 30, 95447, Bayreuth, Germany
| | - Markus Retsch
- Department of Chemistry, Physical Chemistry I, University of Bayreuth, Universitätsstr. 30, 95447, Bayreuth, Germany
- Bavarian Center for Battery Technology (BayBatt), Weiherstraße 26, 95448, Bayreuth, Germany
- Bavarian Polymer Institute (BPI), Bayreuth Center for Colloids and Interfaces (BZKG), Universitätsstraße 30, 95447, Bayreuth, Germany
| | - George Fytas
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
- Institute of Electronic Structure and Laser, FORTH, N. Plastira 100, Heraklion, 70013, Greece
| | - Bartlomiej Graczykowski
- Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznanskiego 2, Poznan, 61-614, Poland
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
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2
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Diego M, Pirro M, Kim B, Anufriev R, Nomura M. Tailoring Phonon Dispersion of a Genetically Designed Nanophononic Metasurface. ACS NANO 2024; 18:18307-18313. [PMID: 38958360 PMCID: PMC11256740 DOI: 10.1021/acsnano.4c01954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 05/31/2024] [Accepted: 06/11/2024] [Indexed: 07/04/2024]
Abstract
Phonon engineering at the nanoscale holds immense promise for a myriad of applications. However, the design of phononic devices continues to rely on regular shapes chosen according to long-established simple rules. Here, we demonstrate an inverse design approach to create a two-dimensional phononic metasurface exhibiting a highly anisotropic phonon dispersion along the main axes of the Brillouin zone. A partial hypersonic bandgap of approximately 3.5 GHz is present along one axis, with gap closure along the orthogonal axis. Such a level of control is achieved through genetically optimized unit cells, with shapes exceeding conventional intuition. We experimentally validated our theoretical predictions using Brillouin light scattering, confirming the effectiveness of the inverse design method. Our approach unlocks the potential for automated engineering of phononic metasurfaces with on-demand functionalities, thus leading toward innovative phononic devices beyond the limitations of traditional design paradigms.
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Affiliation(s)
- Michele Diego
- Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan
| | - Matteo Pirro
- Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan
| | - Byunggi Kim
- Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan
| | - Roman Anufriev
- Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan
| | - Masahiro Nomura
- Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan
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3
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Cang Y, Sainidou R, Rembert P, Matyjaszewski K, Bockstaller M, Graczykowski B, Fytas G. Architecture Controls Phonon Propagation in All-Solid Brush Colloid Metamaterials. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023:e2304157. [PMID: 37972268 DOI: 10.1002/smll.202304157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 10/27/2023] [Indexed: 11/19/2023]
Abstract
Brillouin light scattering and elastodynamic theory are concurrently used to determine and interpret the hypersonic phonon dispersion relations in brush particle solids as a function of the grafting density with perspectives in optomechanics, heat management, and materials metrology. In the limit of sparse grafting density, the phonon dispersion relations bear similarity to polymer-embedded colloidal assembly structures in which phonon dispersion can be rationalized on the basis of perfect boundary conditions, i.e., isotropic stiffness transitions across the particle interface. In contrast, for dense brush assemblies, more complex dispersion characteristics are observed that imply anisotropic stiffness transition across the particle/polymer interface. This provides direct experimental validation of phonon propagation changes associated with chain conformational transitions in dense particle brush materials. A scaling relation between interface tangential stiffness and crowding of polymer tethers is derived that provides a guideline for chemists to design brush particle materials with tailored phononic dispersion characteristics. The results emphasize the role of interfaces in composite materials systems. Given the fundamental relevance of phonon dispersion to material properties such as thermal transport or mechanical properties, it is also envisioned that the results will spur the development of novel functional hybrid materials.
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Affiliation(s)
- Yu Cang
- School of Aerospace Engineering and Applied Mechanics, Tongji University, Zhangwu Road 100, Shanghai, 200092, China
| | - Rebecca Sainidou
- Laboratoire Ondes et Milieux Complexes UMR CNRS 6294, UNIHAVRE, Normandie University, 75 rue Bellot, Le Havre, F-76600, France
| | - Pascal Rembert
- Laboratoire Ondes et Milieux Complexes UMR CNRS 6294, UNIHAVRE, Normandie University, 75 rue Bellot, Le Havre, F-76600, France
| | - Krzysztof Matyjaszewski
- Chemistry Department, Carnegie Mellon University, 4400 Forbes Avenue, Pittsburgh, PA, 15213, USA
| | - Michael Bockstaller
- Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA
| | - Bartlomiej Graczykowski
- Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznanskiego 2, Poznan, 61-614, Poland
| | - George Fytas
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
- Institute of Electronic Structure and Laser, FORTH, N. Plastira 100, Heraklion, 70013, Greece
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4
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Kim H, Gueddida A, Wang Z, Djafari-Rouhani B, Fytas G, Furst EM. Tunable Hypersonic Bandgap Formation in Anisotropic Crystals of Dumbbell Nanoparticles. ACS NANO 2023; 17:19224-19231. [PMID: 37756140 PMCID: PMC10569095 DOI: 10.1021/acsnano.3c05750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 09/20/2023] [Indexed: 09/29/2023]
Abstract
Phononic materials exhibit mechanical properties that alter the propagation of acoustic waves and are widely useful for metamaterials. To fabricate acoustic materials with phononic bandgaps, colloidal nanoparticles and their assemblies allow access to various crystallinities in the submicrometer scale. We fabricated anisotropic crystals with dumbbell-shaped nanoparticles via field-directed self-assembly. Brillouin light spectroscopy detected the formation of direction-dependent hypersonic phononic bandgaps that scale with the lattice parameters. In addition, the local resonances of the constituent nanoparticles enable metamaterial behavior by opening hybridization gaps in disordered structures. Unexpectedly, this bandgap frequency is robust to changes in the dumbbell aspect ratio. Overall, this study provides a structure-property relationship for designing anisotropic phononic materials with targeted phononic bandgaps.
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Affiliation(s)
- Hojin Kim
- Department
of Chemical & Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Abdellatif Gueddida
- Institut
d’Electronique, de Microélectronique et de Nanotechnologie
(IEMN), UMR-CNRS 8520, Département de Physique, Université de Lille, F-59655, Villeneuve d’Ascq, France
| | - Zuyuan Wang
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Bahram Djafari-Rouhani
- Institut
d’Electronique, de Microélectronique et de Nanotechnologie
(IEMN), UMR-CNRS 8520, Département de Physique, Université de Lille, F-59655, Villeneuve d’Ascq, France
| | - George Fytas
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- Institute
of Electronic Structure and Laser, Foundation for Research
and Technology-Hellas (FORTH), 71110 Heraklion, Greece
| | - Eric M. Furst
- Department
of Chemical & Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
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5
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Cang Y, Sainidou R, Rembert P, Magnabosco G, Still T, Vogel N, Graczykowski B, Fytas G. Origin of the Acoustic Bandgaps in Hypersonic Colloidal Phononics: The Role of the Elastic Impedance. J Phys Chem B 2022; 126:6575-6584. [PMID: 35997523 PMCID: PMC9442645 DOI: 10.1021/acs.jpcb.2c03923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 08/11/2022] [Indexed: 11/30/2022]
Abstract
How phonons propagate in nanostructures determines the flow of elastic and thermal energy in dielectric materials. However, a reliable theoretical prediction of the phonon dispersion relation requires experimental verification both near to and far from the Brillouin zone of the nanostructure. We report on the experimental hypersonic phonon dispersion of hard (SiO2) and soft (polymer) fcc colloidal crystals infiltrated in liquid polydimethylsiloxane with different elastic impedance contrast using Brillouin light spectroscopy. We discuss the distinct differences with first-principles full elastodynamic calculations involving a multiple-scattering theory. Interparticle contacts strongly impact the long-wavelength speed of sound and the nature of the particle vibration resonance-induced hybridization hypersonic bandgap. The absence of the order-induced Bragg bandgap in SiO2 and its presence in soft opals cannot be fully accounted for by the theory, limiting its predictive power. Bridging the elasticity of the two colloidal crystals with suitable SiO2 core-shell (polymer) particles reveals an unprecedented crossover behavior in the dispersion relation. In view of many conversational parameters, the control tuning of phonon propagation in soft matter-based hypersonic phononics remains challenging.
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Affiliation(s)
- Yu Cang
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- School
of Aerospace Engineering and Applied Mechanics, Tongji University, Zhangwu
Road 100, Shanghai 200092, China
| | - Rebecca Sainidou
- Laboratoire
Ondes et Milieux Complexes UMR CNRS 6294, UNIHAVRE, Normandie University, 75 rue Bellot, F-76600 Le Havre, France
| | - Pascal Rembert
- Laboratoire
Ondes et Milieux Complexes UMR CNRS 6294, UNIHAVRE, Normandie University, 75 rue Bellot, F-76600 Le Havre, France
| | - Giulia Magnabosco
- Institute
of Particle Technology, Friedrich-Alexander
University Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Tim Still
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Nicolas Vogel
- Institute
of Particle Technology, Friedrich-Alexander
University Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Bartlomiej Graczykowski
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- Faculty
of Physics, Adam Mickiewicz University, Uniwersytetu Poznanskiego 2, Poznan 61-614, Poland
| | - George Fytas
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- Institute
of Electronic Structure and Laser, FO.R.T.H, N. Plastira 100, /0013, Heraklion 71110, Greece
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6
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Wang Z, Kim H, Secchi M, Montagna M, Furst EM, Djafari-Rouhani B, Fytas G. Quantization of Acoustic Modes in Dumbbell Nanoparticles. PHYSICAL REVIEW LETTERS 2022; 128:048003. [PMID: 35148122 DOI: 10.1103/physrevlett.128.048003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 01/05/2022] [Indexed: 06/14/2023]
Abstract
The vibrational eigenmodes of dumbbell-shaped polystyrene nanoparticles are recorded by Brillouin light spectroscopy (BLS), and the full experimental spectra are calculated theoretically. Different from spheres with a degeneracy of (2l+1), with l being the angular momentum quantum number, the eigenmodes of dumbbells are either singly or doubly degenerate owing to their axial symmetry. The BLS spectrum reveals a new, low-frequency peak, which is attributed to the out-of-phase vibration of the two lobes of the dumbbell. The quantization of acoustic modes in these molecule-shaped dumbbell particles evolves from the primary colloidal spheres as the separation between the two lobes increases.
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Affiliation(s)
- Zuyuan Wang
- Max Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
- Institute for Measurement and Automation, Division of Sensor Technology and Measurement Systems, Bundeswehr University Munich, Werner Heisenberg Weg 39, 85579 Neubiberg, Germany
| | - Hojin Kim
- Department of Chemical & Biomolecular Engineering, Allan P. Colburn Laboratory, University of Delaware, Newark, Delaware 19716, USA
| | - Maria Secchi
- Department of Industrial Engineering, University of Trento, via Sommarive 9, I-38123 Trento, Italy
| | - Maurizio Montagna
- Dipartimento di Fisica, Universitá di Trento, via Sommarive 14, I-38123 Trento, Italy
| | - Eric M Furst
- Department of Chemical & Biomolecular Engineering, Allan P. Colburn Laboratory, University of Delaware, Newark, Delaware 19716, USA
| | - Bahram Djafari-Rouhani
- Institut d'Électronique, de Microélectronique et de Nanotechnologie (IEMN), UMRCNRS 8520, Department of Physics, University of Lille, Villeneuve d'Ascq 59655, France
| | - George Fytas
- Max Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
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7
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Lifting restrictions on coherence loss when characterizing non-transparent hypersonic phononic crystals. Sci Rep 2021; 11:17174. [PMID: 34433886 PMCID: PMC8387379 DOI: 10.1038/s41598-021-96663-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 08/10/2021] [Indexed: 11/09/2022] Open
Abstract
Hypersonic phononic bandgap structures confine acoustic vibrations whose wavelength is commensurate with that of light, and have been studied using either time- or frequency-domain optical spectroscopy. Pulsed pump-probe lasers are the preferred instruments for characterizing periodic multilayer stacks from common vacuum deposition techniques, but the detection mechanism requires the injected sound wave to maintain coherence during propagation. Beyond acoustic Bragg mirrors, frequency-domain studies using a tandem Fabry–Perot interferometer (TFPI) find dispersions of two- and three-dimensional phononic crystals (PnCs) even for highly disordered samples, but with the caveat that PnCs must be transparent. Here, we demonstrate a hybrid technique for overcoming the limitations that time- and frequency-domain approaches exhibit separately. Accordingly, we inject coherent phonons into a non-transparent PnC using a pulsed laser and acquire the acoustic transmission spectrum on a TFPI, where pumped appear alongside spontaneously excited (i.e. incoherent) phonons. Choosing a metallic Bragg mirror for illustration, we determine the bandgap and compare with conventional time-domain spectroscopy, finding resolution of the hybrid approach to match that of a state-of-the-art asynchronous optical sampling setup. Thus, the hybrid pump–probe technique retains key performance features of the established one and going forward will likely be preferred for disordered samples.
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8
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Kim H, Sau M, Furst EM. An Expanded State Diagram for the Directed Self-Assembly of Colloidal Suspensions in Toggled Fields. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:9926-9934. [PMID: 32697093 DOI: 10.1021/acs.langmuir.0c01616] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The suspension structure and assembly kinetics of micrometer-diameter paramagnetic spheres in toggled magnetic fields are investigated at a constant field strength H = 1750A·m-1 while toggling the field on and off over the frequency range 0.3<f<5 Hz and duty ratio values (the fraction of time the field is on over one toggle period) 0.05 ≤ ξ ≤ 0.8. Five microstructures form after sufficient time in the toggled field, fluid, columnar, percolated, ellipsoidal-shaped, and perpendicular, and their kinetic pathways are identified. For ellipsoidal-shaped microstructures, diffusion-driven particle aggregation at early times gives way to a fluid-like breakup. For columnar and percolated structures, this coarsening arrests before breakup. As the toggling duty cycle decreases, the range of frequencies for each structure narrows, giving way to an unstructured fluid; below ξ<0.1, only the fluid state is observed. The existence of fluid, columnar, percolated, and ellipsoidal-shaped microstructures agrees well with those predicted by the theoretical and computational work of Sherman et al. (Sherman, Z. M.; Rosenthal, H.; Swan, J. W. Langmuir 2018, 34, 1029-1041). Microstructures that connect perpendicularly to the magnetic field are identified for 0.1 ≤ ξ ≤ 0.3 and 1.6<f<3.7 Hz. Perpendicular microstructures also exhibit emergent dynamics with continuous rotation, breakup, and coalescence events.
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Affiliation(s)
- Hojin Kim
- Department of Chemical and Biomolecular Engineering, Allan P. Colburn Laboratory, University of Delaware, Newark, Delaware 19716, United States
| | - Moujhuri Sau
- Department of Chemical and Biomolecular Engineering, Allan P. Colburn Laboratory, University of Delaware, Newark, Delaware 19716, United States
| | - Eric M Furst
- Department of Chemical and Biomolecular Engineering, Allan P. Colburn Laboratory, University of Delaware, Newark, Delaware 19716, United States
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9
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Graczykowski B, Vogel N, Bley K, Butt HJ, Fytas G. Multiband Hypersound Filtering in Two-Dimensional Colloidal Crystals: Adhesion, Resonances, and Periodicity. NANO LETTERS 2020; 20:1883-1889. [PMID: 32017578 PMCID: PMC7068716 DOI: 10.1021/acs.nanolett.9b05101] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 01/29/2020] [Indexed: 05/27/2023]
Abstract
The hypersonic phonon propagation in large-area two-dimensional colloidal crystals is probed by spontaneous micro Brillouin light scattering. The dispersion relation of thermally populated Lamb waves reveals multiband filtering due to three distinct types of acoustic band gaps. We find Bragg gaps accompanied by two types of hybridization gaps in both sub- and superwavelength regimes resulting from contact-based resonances and nanoparticle eigenmodes, respectively. The operating GHz frequencies can be tuned by particle size and depend on the adhesion at the contact interfaces. The experimental dispersion relations are well represented by a finite element method model enabling identification of observed modes. The presented approach also allows for contactless study of the contact stiffness of submicrometer particles, which reveals size effect deviating from macroscopic predictions.
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Affiliation(s)
- Bartlomiej Graczykowski
- Faculty
of Physics, Adam Mickiewicz University, Uniwersytetu Poznanskiego 2, 61-614 Poznan, Poland
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Nicolas Vogel
- Institute
of Particle Technology, Friedrich-Alexander
University Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Karina Bley
- Institute
of Particle Technology, Friedrich-Alexander
University Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Hans-Jürgen Butt
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - George Fytas
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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10
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Kang E, Graczykowski B, Jonas U, Christie D, Gray LAG, Cangialosi D, Priestley RD, Fytas G. Shell Architecture Strongly Influences the Glass Transition, Surface Mobility, and Elasticity of Polymer Core-Shell Nanoparticles. Macromolecules 2019; 52:5399-5406. [PMID: 31367064 PMCID: PMC6659035 DOI: 10.1021/acs.macromol.9b00766] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 06/14/2019] [Indexed: 01/29/2023]
Abstract
Despite the growing application of nanostructured polymeric materials, there still remains a large gap in our understanding of polymer mechanics and thermal stability under confinement and near polymer-polymer interfaces. In particular, the knowledge of polymer nanoparticle thermal stability and mechanics is of great importance for their application in drug delivery, phononics, and photonics. Here, we quantified the effects of a polymer shell layer on the modulus and glass-transition temperature (T g) of polymer core-shell nanoparticles via Brillouin light spectroscopy and modulated differential scanning calorimetry, respectively. Nanoparticles consisting of a polystyrene (PS) core and shell layers of poly(n-butyl methacrylate) (PBMA) were characterized as model systems. We found that the high T g of the PS core was largely unaffected by the presence of an outer polymer shell, whereas the lower T g of the PBMA shell layer decreased with increasing PBMA thickness. The surface mobility was revealed at a temperature about 15 K lower than the T g of the PBMA shell layer. Overall, the modulus of the core-shell nanoparticles decreased with increasing PBMA shell layer thickness. These results suggest that the nanoparticle modulus and T g can be tuned independently through the control of nanoparticle composition and architecture.
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Affiliation(s)
- Eunsoo Kang
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Bartlomiej Graczykowski
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- Faculty
of Physics, Adam Mickiewicz University, Umultowska 85, 61614 Poznan, Poland
| | - Ulrich Jonas
- Department
of Chemistry and Biology, University of
Siegen, Adolf-Reichwein-Strasse 2, 57076 Siegen, Germany
| | - Dane Christie
- Department
of Chemical and Biological Engineering and Princeton Institute for the Science
and Technology of Materials, Princeton University, Princeton, New Jersey 08544, United States
| | - Laura A. G. Gray
- Department
of Chemical and Biological Engineering and Princeton Institute for the Science
and Technology of Materials, Princeton University, Princeton, New Jersey 08544, United States
| | - Daniele Cangialosi
- Centro
de
Física de Materiales (CSIC-UPV/EHU), Paseo Manuel de Lardizabal 5, 20018 San Sebastián, Spain
- Donostia
International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain
| | - Rodney D. Priestley
- Department
of Chemical and Biological Engineering and Princeton Institute for the Science
and Technology of Materials, Princeton University, Princeton, New Jersey 08544, United States
| | - George Fytas
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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11
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Abi Ghanem M, Khanolkar A, Wallen SP, Helwig M, Hiraiwa M, Maznev AA, Vogel N, Boechler N. Longitudinal eigenvibration of multilayer colloidal crystals and the effect of nanoscale contact bridges. NANOSCALE 2019; 11:5655-5665. [PMID: 30865190 DOI: 10.1039/c8nr08453j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Longitudinal contact-based vibrations of colloidal crystals with a controlled layer thickness are studied. These crystals consist of 390 nm diameter polystyrene spheres arranged into close packed, ordered lattices with a thickness of one to twelve layers. Using laser ultrasonics, eigenmodes of the crystals that have out-of-plane motion are excited. The particle-substrate and effective interlayer contact stiffnesses in the colloidal crystals are extracted using a discrete, coupled oscillator model. Extracted stiffnesses are correlated with scanning electron microscope images of the contacts and atomic force microscope characterization of the substrate surface topography after removal of the spheres. Solid bridges of nanometric thickness are found to drastically alter the stiffness of the contacts, and their presence is found to be dependent on the self-assembly process. Measurements of the eigenmode quality factors suggest that energy leakage into the substrate plays a role for low frequency modes but is overcome by disorder- or material-induced losses at higher frequencies. These findings help further the understanding of the contact mechanics, and the effects of disorder in three-dimensional micro- and nano-particulate systems, and open new avenues to engineer new types of micro- and nanostructured materials with wave tailoring functionalities via control of the adhesive contact properties.
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Affiliation(s)
- Maroun Abi Ghanem
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA, 92093 USA.
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12
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Kang E, Kim H, Gray LAG, Christie D, Jonas U, Graczykowski B, Furst EM, Priestley RD, Fytas G. Ultrathin Shell Layers Dramatically Influence Polymer Nanoparticle Surface Mobility. Macromolecules 2018; 51:8522-8529. [PMID: 30906073 PMCID: PMC6428372 DOI: 10.1021/acs.macromol.8b01804] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 10/01/2018] [Indexed: 01/27/2023]
Abstract
Advances in nanoparticle synthesis, self-assembly, and surface coating or patterning have enabled a diverse array of applications ranging from photonic and phononic crystal fabrication to drug delivery vehicles. One of the key obstacles restricting its potential is structural and thermal stability. The presence of a glass transition can facilitate deformation within nanoparticles, thus resulting in a significant alteration in structure and performance. Recently, we detected a glassy-state transition within individual polystyrene nanoparticles and related its origin to the presence of a surface layer with enhanced dynamics compared to the bulk. The presence of this mobile layer could have a dramatic impact on the thermal stability of polymer nanoparticles. Here, we demonstrate how the addition of a shell layer, as thin as a single polymer chain, atop the nanoparticles could completely eliminate any evidence of enhanced mobility at the surface of polystyrene nanoparticles. The ultrathin polymer shell layers were placed atop the nanoparticles via two approaches: (i) covalent bonding or (ii) electrostatic interactions. The temperature dependence of the particle vibrational spectrum, as recorded by Brillouin light scattering, was used to probe the surface mobility of nanoparticles with and without a shell layer. Beyond suppression of the surface mobility, the presence of the ultrathin polymer shell layers impacted the nanoparticle glass transition temperature and shear modulus, albeit to a lesser extent. The implication of this work is that the core-shell architecture allows for tailoring of the nanoparticle elasticity, surface softening, and glass transition temperature.
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Affiliation(s)
- Eunsoo Kang
- Max Planck Institute
for Polymer Research, Ackermannweg
10, 55128 Mainz, Germany
| | - Hojin Kim
- Department
of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Laura A. G. Gray
- Department
of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Dane Christie
- Department
of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Ulrich Jonas
- Macromolecular
Chemistry, Department of Chemistry and Biology, University of Siegen, Adolf-Reichwein-Strasse 2, 57076 Siegen, Germany
| | | | - Eric M. Furst
- Department
of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Rodney D. Priestley
- Department
of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - George Fytas
- Max Planck Institute
for Polymer Research, Ackermannweg
10, 55128 Mainz, Germany
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13
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Streque J, Rouxel D, Talbi A, Thomassey M, Vincent B. Low-Temperature Variation of Acoustic Velocity in PDMS for High-Frequency Applications. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2018; 65:862-869. [PMID: 29733288 DOI: 10.1109/tuffc.2018.2814541] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Polydimethylsiloxane (PDMS) and other related silicon-based polymers are among the most widely employed elastomeric materials in microsystems, owing to their physical and chemical properties. Meanwhile, surface acoustic wave (SAW) and bulk acoustic wave (BAW) sensors and filters have been vastly explored for sensing and wireless applications. Many fields could benefit from the combined use of acoustic wave devices, and polydimethylsiloxane-based soft-substrates, microsystems, or packaging elements. The mechanical constants of PDMS strongly depend on frequency, similar to rubber materials. This brings to the exploration of the specific mechanical properties of PDMS encountered at high frequency, required for its exploitation in SAW or BAW devices. First, low-frequency mechanical behavior is confirmed from stress strain measurements, remaining useful for the exploitation of PDMS as a soft substrate or packaging material. The study, then, proposes a temperature-dependent, high-frequency mechanical study of PDMS based on Brillouin spectroscopy to determine the evolution of the longitudinal acoustic velocity in this material, which constitutes the main mechanical parameter for the design of acoustic wave devices. The PDMS glass transition is then retrieved by differential scanning calorimetry in order to confirm the observations made by Brillouin spectroscopy. This paper validates Brillouin spectroscopy as a very suitable characterization technique for the retrieval of longitudinal mechanical properties at low temperature, as a preliminary investigation for the design of acoustic wave devices coupled with soft materials.
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14
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Nutz FA, Philipp A, Kopera BAF, Dulle M, Retsch M. Low Thermal Conductivity through Dense Particle Packings with Optimum Disorder. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1704910. [PMID: 29484721 DOI: 10.1002/adma.201704910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2017] [Revised: 11/24/2017] [Indexed: 06/08/2023]
Abstract
Heat transport plays a critical role in modern batteries, electrodes, and capacitors. This is caused by the ongoing miniaturization of such nanotechnological devices, which increases the local power density and hence temperature. Even worse, the introduction of heterostructures and interfaces is often accompanied by a reduction in thermal conductivity, which can ultimately lead to the failure of the entire device. Surprisingly, a fundamental understanding of the governing heat transport processes even in simple systems, such as binary particle mixtures is still missing. This contribution closes this gap and elucidates how strongly the polydispersity of a model particulate system influences the effective thermal conductivity across such a heterogeneous system. In a combined experimental and modeling approach, well-defined mixtures of monodisperse particles with varying size ratios are investigated. The transition from order to disorder can reduce the effective thermal conductivity by as much as ≈50%. This is caused by an increase in the thermal transport path length and is governed by the number of interparticle contact points. These results are of general importance for many particulate and heterostructured materials and will help to conceive improved device layouts with more reliable heat dissipation or conservation properties in the future.
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Affiliation(s)
- Fabian A Nutz
- Department of Chemistry, University of Bayreuth, Universitaetsstr. 30, 95447, Bayreuth, Germany
| | - Alexandra Philipp
- Department of Chemistry, University of Bayreuth, Universitaetsstr. 30, 95447, Bayreuth, Germany
| | - Bernd A F Kopera
- Department of Chemistry, University of Bayreuth, Universitaetsstr. 30, 95447, Bayreuth, Germany
| | - Martin Dulle
- JCNS-1/ICS-1: Neutron Scattering, Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Straße, 52428, Jülich, Germany
| | - Markus Retsch
- Department of Chemistry, University of Bayreuth, Universitaetsstr. 30, 95447, Bayreuth, Germany
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15
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Nutz FA, Retsch M. Interfacial and volumetric sensitivity of the dry sintering process of polymer colloidal crystals: a thermal transport and photonic bandgap study. Phys Chem Chem Phys 2018; 19:16124-16130. [PMID: 28604861 DOI: 10.1039/c7cp01994g] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We introduce the in situ characterization of the dry sintering process of face-centred cubic colloidal crystals by two complementary techniques: thermal transport and photonic stopband characterization. Therefore, we employed time-dependent, isothermal laser flash analysis and specular reflectivity experiments close to the glass transition temperature of the colloidal crystal. Both methods yield distinctly different time constants of the film formation process. This discrepancy can be attributed to a volume- (photonic stopband) and interface-driven (thermal transport) sensitivity of the respective characterization method. Nevertheless, both methods yield comparable apparent activation energies. Finally, we extended the sintering process characterization to further polymer compositions, with vastly different glass transition temperatures. We could show that the film formation rate is governed by the viscoelastic properties of the polymers at the respective annealing temperature.
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Affiliation(s)
- Fabian A Nutz
- University of Bayreuth, Physical Chemistry - Polymer Systems, Universitaetsstr. 30, 95447 Bayreuth, Germany.
| | - Markus Retsch
- University of Bayreuth, Physical Chemistry - Polymer Systems, Universitaetsstr. 30, 95447 Bayreuth, Germany.
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16
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17
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Nutz FA, Retsch M. Tailor-made temperature-dependent thermal conductivity via interparticle constriction. SCIENCE ADVANCES 2017; 3:eaao5238. [PMID: 29159286 PMCID: PMC5693563 DOI: 10.1126/sciadv.aao5238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Accepted: 10/19/2017] [Indexed: 06/07/2023]
Abstract
Managing heat is a major challenge to meet future demands for a sustainable use of our energy resources. This requires materials, which can be custom-designed to exhibit specific temperature-dependent thermal transport properties to become integrated into thermal switches, transistors, or diodes. Common crystalline and amorphous materials are not suitable, owing to their gradual changes of the temperature-dependent thermal conductivity. We show how a second-order phase transition fully controls the temperature-dependent thermal transport properties of polymer materials. We demonstrate four major concepts based on a colloidal superstructure: (i) control of transition temperature, (ii) width of phase transition regime, (iii) multistep transitions, and (iv) step height of the transition. Most importantly, this unique control over thermal conductivity is only governed by the interparticle constriction, the particle composition, and its mesostructure. Our concept is therefore also applicable to a wide variety of other particulate materials.
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Affiliation(s)
- Fabian A. Nutz
- Department of Chemistry, University of Bayreuth, Universitaetsstraβe 30, 95447 Bayreuth, Germany
| | - Markus Retsch
- Department of Chemistry, University of Bayreuth, Universitaetsstraβe 30, 95447 Bayreuth, Germany
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18
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Bolmatov D, Zhernenkov M, Sharpnack L, Agra-Kooijman DM, Kumar S, Suvorov A, Pindak R, Cai YQ, Cunsolo A. Emergent Optical Phononic Modes upon Nanoscale Mesogenic Phase Transitions. NANO LETTERS 2017; 17:3870-3876. [PMID: 28548861 DOI: 10.1021/acs.nanolett.7b01324] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The investigation of phononic collective excitations in soft matter systems at the molecular scale has always been challenging due to limitations of experimental techniques in resolving low-energy modes. Recent advances in inelastic X-ray scattering (IXS) enabled the study of such systems with unprecedented spectral contrast at meV excitation energies. In particular, it has become possible to shed light on the low-energy collective motions in materials whose morphology and phase behavior can easily be manipulated, such as mesogenic systems. The understanding of collective mode behavior with a Q-dependence is the key to implement heat management based on the control of a sample structure. The latter has great potential for a large number of energy-inspired innovations. As a first step toward this goal, we carried out high contrast IXS measurements on a liquid crystal sample, D7AOB, which exhibits solid-like dynamic features, such as the coexistence of longitudinal and transverse phononic modes. For the first time, we found that these terahertz phononic excitations persist in the crystal, smectic A, and isotropic phases. Furthermore, the intermediate smectic A phase is shown to support a van der Waals-mediated nonhydrodynamic mode with an optical-like phononic behavior. The tunability of the collective excitations at nanometer-terahertz scales via selection of the sample mesogenic phase represents a new opportunity to manipulate optomechanical properties of soft metamaterials.
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Affiliation(s)
- Dima Bolmatov
- National Synchrotron Light Source II, Brookhaven National Laboratory , Upton, New York 11973, United States
| | - Mikhail Zhernenkov
- National Synchrotron Light Source II, Brookhaven National Laboratory , Upton, New York 11973, United States
| | - Lewis Sharpnack
- Department of Physics, Kent State University , Kent, Ohio 44242, United States
| | | | - Satyendra Kumar
- Department of Physics, Kent State University , Kent, Ohio 44242, United States
- Division of Research and Department of Physics, University at Albany , Albany, New York 12222, United States
| | - Alexey Suvorov
- National Synchrotron Light Source II, Brookhaven National Laboratory , Upton, New York 11973, United States
| | - Ronald Pindak
- National Synchrotron Light Source II, Brookhaven National Laboratory , Upton, New York 11973, United States
| | - Yong Q Cai
- National Synchrotron Light Source II, Brookhaven National Laboratory , Upton, New York 11973, United States
| | - Alessandro Cunsolo
- National Synchrotron Light Source II, Brookhaven National Laboratory , Upton, New York 11973, United States
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19
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Probing Dynamics in Colloidal Crystals with Pump-Probe Experiments at LCLS: Methodology and Analysis. APPLIED SCIENCES-BASEL 2017. [DOI: 10.3390/app7050519] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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20
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Schneider D, Gomopoulos N, Koh CY, Papadopoulos P, Kremer F, Thomas EL, Fytas G. Nonlinear control of high-frequency phonons in spider silk. NATURE MATERIALS 2016; 15:1079-83. [PMID: 27454046 DOI: 10.1038/nmat4697] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 06/15/2016] [Indexed: 05/26/2023]
Abstract
Spider dragline silk possesses superior mechanical properties compared with synthetic polymers with similar chemical structure due to its hierarchical structure comprised of partially crystalline oriented nanofibrils. To date, silk's dynamic mechanical properties have been largely unexplored. Here we report an indirect hypersonic phononic bandgap and an anomalous dispersion of the acoustic-like branch from inelastic (Brillouin) light scattering experiments under varying applied elastic strains. We show the mechanical nonlinearity of the silk structure generates a unique region of negative group velocity, that together with the global (mechanical) anisotropy provides novel symmetry conditions for gap formation. The phononic bandgap and dispersion show strong nonlinear strain-dependent behaviour. Exploiting material nonlinearity along with tailored structural anisotropy could be a new design paradigm to access new types of dynamic behaviour.
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Affiliation(s)
- Dirk Schneider
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Nikolaos Gomopoulos
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Cheong Y Koh
- Functional and Smart Materials Laboratory, Emerging Systems, DSO National Laboratories, S117605 Singapore, Singapore
| | - Periklis Papadopoulos
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- Department of Physics, University of Ioannina, 45110 Ioannina, Greece
| | - Friedrich Kremer
- Institute of Experimental Physics I, Linnéstr. 5, University of Leipzig, 04103 Leipzig, Germany
| | - Edwin L Thomas
- Department of Materials Science and Nano-Engineering, Rice University, Houston, Texas 77030, USA
| | - George Fytas
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- Department of Materials Science University of Crete and IESL-F.O.R.T.H, 77110 Heraklion, Greece
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21
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Wagner MR, Graczykowski B, Reparaz JS, El Sachat A, Sledzinska M, Alzina F, Sotomayor Torres CM. Two-Dimensional Phononic Crystals: Disorder Matters. NANO LETTERS 2016; 16:5661-5668. [PMID: 27580163 DOI: 10.1021/acs.nanolett.6b02305] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The design and fabrication of phononic crystals (PnCs) hold the key to control the propagation of heat and sound at the nanoscale. However, there is a lack of experimental studies addressing the impact of order/disorder on the phononic properties of PnCs. Here, we present a comparative investigation of the influence of disorder on the hypersonic and thermal properties of two-dimensional PnCs. PnCs of ordered and disordered lattices are fabricated of circular holes with equal filling fractions in free-standing Si membranes. Ultrafast pump and probe spectroscopy (asynchronous optical sampling) and Raman thermometry based on a novel two-laser approach are used to study the phononic properties in the gigahertz (GHz) and terahertz (THz) regime, respectively. Finite element method simulations of the phonon dispersion relation and three-dimensional displacement fields furthermore enable the unique identification of the different hypersonic vibrations. The increase of surface roughness and the introduction of short-range disorder are shown to modify the phonon dispersion and phonon coherence in the hypersonic (GHz) range without affecting the room-temperature thermal conductivity. On the basis of these findings, we suggest a criteria for predicting phonon coherence as a function of roughness and disorder.
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Affiliation(s)
- Markus R Wagner
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology , Campus UAB, Bellaterra, 08193 Barcelona, Spain
| | - Bartlomiej Graczykowski
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology , Campus UAB, Bellaterra, 08193 Barcelona, Spain
| | - Juan Sebastian Reparaz
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology , Campus UAB, Bellaterra, 08193 Barcelona, Spain
| | - Alexandros El Sachat
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology , Campus UAB, Bellaterra, 08193 Barcelona, Spain
| | - Marianna Sledzinska
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology , Campus UAB, Bellaterra, 08193 Barcelona, Spain
| | - Francesc Alzina
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology , Campus UAB, Bellaterra, 08193 Barcelona, Spain
| | - Clivia M Sotomayor Torres
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology , Campus UAB, Bellaterra, 08193 Barcelona, Spain
- ICREA - Catalan Institute for Research and Advanced Studies , 08010 Barcelona, Spain
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22
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23
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Formation of Bragg Band Gaps in Anisotropic Phononic Crystals Analyzed With the Empty Lattice Model. CRYSTALS 2016. [DOI: 10.3390/cryst6050052] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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24
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Alonso-Redondo E, Schmitt M, Urbach Z, Hui CM, Sainidou R, Rembert P, Matyjaszewski K, Bockstaller MR, Fytas G. A new class of tunable hypersonic phononic crystals based on polymer-tethered colloids. Nat Commun 2015; 6:8309. [PMID: 26390851 PMCID: PMC4595630 DOI: 10.1038/ncomms9309] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 08/11/2015] [Indexed: 11/09/2022] Open
Abstract
The design and engineering of hybrid materials exhibiting tailored phononic band gaps are fundamentally relevant to innovative material technologies in areas ranging from acoustics to thermo-optic devices. Phononic hybridization gaps, originating from the anti-crossing between local resonant and propagating modes, have attracted particular interest because of their relative robustness to structural disorder and the associated benefit to 'manufacturability'. Although hybridization gap materials are well known, their economic fabrication and efficient control of the gap frequency have remained elusive because of the limited property variability and expensive fabrication methodologies. Here we report a new strategy to realize hybridization gap materials by harnessing the 'anisotropic elasticity' across the particle-polymer interface in densely polymer-tethered colloidal particles. Theoretical and Brillouin scattering analysis confirm both the robustness to disorder and the tunability of the resulting hybridization gap and provide guidelines for the economic synthesis of new materials with deliberately controlled gap position and width frequencies.
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Affiliation(s)
- E. Alonso-Redondo
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - M. Schmitt
- Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, USA
| | - Z. Urbach
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - C. M. Hui
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, USA
| | - R. Sainidou
- Laboratoire Ondes et Milieux Complexes, UMR CNRS 6294, University of Le Havre, 75 Rue Bellot, 76600 Le Havre, France
| | - P. Rembert
- Laboratoire Ondes et Milieux Complexes, UMR CNRS 6294, University of Le Havre, 75 Rue Bellot, 76600 Le Havre, France
| | - K. Matyjaszewski
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, USA
| | - M. R. Bockstaller
- Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, USA
| | - G. Fytas
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- Department of Materials Science, FORTH-IESL, PO Box 1527, 71110 Heraklion, Greece
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25
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Wright OB, Matsuda O. Watching surface waves in phononic crystals. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2015. [PMID: 26217053 DOI: 10.1098/rsta.2014.0364] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
In this paper, we review results obtained by ultrafast imaging of gigahertz surface acoustic waves in surface phononic crystals with one- and two-dimensional periodicities. By use of quasi-point-source optical excitation, we show how, from a series of images that form a movie of the travelling waves, the dispersion relation of the acoustic modes, their corresponding mode patterns and the position and widths of phonon stop bands can be obtained by temporal and spatio-temporal Fourier analysis. We further demonstrate how one can follow the temporal evolution of phononic eigenstates in k-space using data from phononic-crystal waveguides as an example.
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Affiliation(s)
- Oliver B Wright
- Division of Applied Physics, Faculty of Engineering, Hokkaido University, 060-8628 Sapporo, Japan
| | - Osamu Matsuda
- Division of Applied Physics, Faculty of Engineering, Hokkaido University, 060-8628 Sapporo, Japan
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26
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Vogel N, Retsch M, Fustin CA, del Campo A, Jonas U. Advances in Colloidal Assembly: The Design of Structure and Hierarchy in Two and Three Dimensions. Chem Rev 2015; 115:6265-311. [DOI: 10.1021/cr400081d] [Citation(s) in RCA: 531] [Impact Index Per Article: 59.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Nicolas Vogel
- Institute
of Particle Technology, Friedrich-Alexander-University Erlangen-Nuremberg, Cauerstrasse
4, 91058 Erlangen, Germany
- Cluster
of Excellence - Engineering of Advanced Materials, University of Erlangen-Nuremberg, 91054 Erlangen, Germany
| | - Markus Retsch
- Physical
Chemistry 1 - Polymer Systems, University of Bayreuth, Universitätsstraße
30, 95447 Bayreuth, Germany
| | - Charles-André Fustin
- Institute
of Condensed Matter and Nanosciences (IMCN), Bio- and Soft Matter
Division (BSMA), Université catholique de Louvain, Place Louis
Pasteur 1, B-1348 Louvain-la-Neuve, Belgium
| | - Aranzazu del Campo
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Ulrich Jonas
- Macromolecular
Chemistry, Cμ - The Research Center for Micro- and Nanochemistry
and Engineering, University of Siegen, Adolf-Reichwein-Strasse 2, 57076 Siegen, Germany
- Bio-Organic Materials Chemistry Laboratory (BOMCLab), Institute of Electronic Structure & Laser (IESL), Foundation for Research and Technology - Hellas (FORTH), Nikolaou Plastira 100, Vassilika Vouton, P.O. Box 1527, 71110 Heraklion, Crete, Greece
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27
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Polystyrene colloidal crystals: Interface controlled thermal conductivity in an open-porous mesoparticle superstructure. J Colloid Interface Sci 2015; 457:96-101. [PMID: 26160735 DOI: 10.1016/j.jcis.2015.06.022] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2015] [Revised: 05/13/2015] [Accepted: 06/12/2015] [Indexed: 11/22/2022]
Abstract
Colloidal crystals typically consist of sub-micron sized monodisperse particles, which are densely packed on a face centered cubic lattice. While many properties of this material class have been studied over the past decades, little is known about their thermal transport properties. The high amount of interfaces and their small interparticle contact area should result in efficient thermal insulation. Using laser flash analysis we report for the first time on the temperature dependent thermal conductivity of a freestanding 366 nm polystyrene (PS) colloidal crystal. Macroscopic monoliths of these samples were fabricated by colloidal self-assembly. We demonstrate a very low thermal conductivity κ of 51 mW K(-1) m(-1) (κ of bulk PS∼140 mW K(-1) m(-1)). Remarkably, this low thermal conductivity is reached at a comparatively high density of 750 kg m(-3). It can be further increased by almost 300% upon film formation and loss of the colloidal mesostructure. Additionally, this open porous structure is largely independent of the surrounding atmosphere. This can be rationalized by the small size (∼100 nm) of the pores present within this colloidal crystal.
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28
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Beltramo PJ, Schneider D, Fytas G, Furst EM. Anisotropic hypersonic phonon propagation in films of aligned ellipsoids. PHYSICAL REVIEW LETTERS 2014; 113:205503. [PMID: 25432048 DOI: 10.1103/physrevlett.113.205503] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Indexed: 05/24/2023]
Abstract
A material with anisotropic elastic mechanical properties and a direction-dependent hypersonic band gap is fabricated using ac electric field-directed convective self-assembly of colloidal ellipsoids. The frequency of the gap, which is detected in the direction perpendicular to particle alignment and entirely absent parallel to alignment, and the effective sound velocities can be tuned by the particle aspect ratio. We hypothesize that the band gap originates from the primary eigenmode peak, the m-splitted (s,1,2) mode, of the particle resonating with the effective medium. These results reveal the potential for powerful control of the hypersonic phononic band diagram by combining anisotropic particles and self-assembly.
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Affiliation(s)
- Peter J Beltramo
- Department of Chemical & Biomolecular Engineering, Center for Molecular and Engineering Thermodynamics, University of Delaware, Newark, Delaware 19716, USA
| | - Dirk Schneider
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - George Fytas
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany and Department of Materials Science, University of Crete and IESL-FORTH, 71110 Heraklion, Greece
| | - Eric M Furst
- Department of Chemical & Biomolecular Engineering, Center for Molecular and Engineering Thermodynamics, University of Delaware, Newark, Delaware 19716, USA
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29
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Wu S, Zhu G, Zhang JS, Banerjee D, Bass JD, Ling C, Yano K. Anisotropic lattice expansion of three-dimensional colloidal crystals and its impact on hypersonic phonon band gaps. Phys Chem Chem Phys 2014; 16:8921-6. [PMID: 24691556 DOI: 10.1039/c4cp00498a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report anisotropic expansion of self-assembled colloidal polystyrene-poly(dimethylsiloxane) crystals and its impact on the phonon band structure at hypersonic frequencies. The structural expansion was achieved by a multistep infiltration-polymerization process. Such a process expands the interplanar lattice distance 17% after 8 cycles whereas the in-plane distance remains unaffected. The variation of hypersonic phonon band structure induced by the anisotropic lattice expansion was recorded by Brillouin measurements. In the sample before expansion, a phononic band gap between 3.7 and 4.4 GHz is observed; after 17% structural expansion, the gap is shifted to a lower frequency between 3.5 and 4.0 GHz. This study offers a facile approach to control the macroscopic structure of colloidal crystals with great potential in designing tunable phononic devices.
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Affiliation(s)
- Songtao Wu
- Toyota Research Institute of North America, Toyota Motor Engineering and Manufacturing North America, Inc., Ann Arbor, Michigan 48105, USA.
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30
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Otsuka PH, Nanri K, Matsuda O, Tomoda M, Profunser DM, Veres IA, Danworaphong S, Khelif A, Benchabane S, Laude V, Wright OB. Broadband evolution of phononic-crystal-waveguide eigenstates in real- and k-spaces. Sci Rep 2013; 3:3351. [PMID: 24284621 PMCID: PMC3842087 DOI: 10.1038/srep03351] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 11/07/2013] [Indexed: 11/09/2022] Open
Abstract
Control of sound in phononic band-gap structures promises novel control and guiding mechanisms. Designs in photonic systems were quickly matched in phononics, and rows of defects in phononic crystals were shown to guide sound waves effectively. The vast majority of work in such phononic guiding has been in the frequency domain, because of the importance of the phononic dispersion relation in governing acoustic confinement in waveguides. However, frequency-domain studies miss vital information concerning the phase of the acoustic field and eigenstate coupling. Using a wide range of wavevectors k, we implement an ultrafast technique to probe the wave field evolution in straight and L-shaped phononic crystal surface-phonon waveguides in real- and k-space in two spatial dimensions, thus revealing the eigenstate-energy redistribution processes and the coupling between different frequency-degenerate eigenstates. Such use of k-t space is a first in acoustics, and should have other interesting applications such as acoustic-metamaterial characterization.
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Affiliation(s)
- P H Otsuka
- Division of Applied Physics, Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan
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Gratale MD, Yunker PJ, Chen K, Still T, Aptowicz KB, Yodh AG. Phonons in two-dimensional colloidal crystals with bond-strength disorder. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 87:052301. [PMID: 23767534 DOI: 10.1103/physreve.87.052301] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 04/02/2013] [Indexed: 06/02/2023]
Abstract
We study phonon modes in two-dimensional colloidal crystals composed of soft microgel particles with hard polystyrene particle dopants distributed randomly on the triangular lattice. This experimental approach produces close-packed lattices of spheres with random bond strength disorder, i.e., the effective springs coupling nearest neighbors are very stiff, very soft, or of intermediate stiffness. Particle tracking video microscopy and covariance matrix techniques are then employed to derive the phonon modes of the corresponding "shadow" crystals with bond strength disorder as a function of increasing dopant concentration. At low frequencies, hard and soft particles participate equally in the phonon modes, and the samples exhibit Debye-like density of states behavior characteristic of crystals. For mid- and high-frequency phonons, the relative participation of hard versus soft particles in each mode is found to vary systematically with dopant concentration. Additionally, a few localized modes, primarily associated with hard particle motions, are found at the highest frequencies.
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Affiliation(s)
- Matthew D Gratale
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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32
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Panczyk MM, Park JG, Wagner NJ, Furst EM. Two-dimensional directed assembly of dicolloids. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:75-81. [PMID: 23215160 DOI: 10.1021/la303678f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The assembly of ordered dicolloid monolayers is directed by an electric field. The dicolloid particles are polystyrene latex with a maximum equatorial diameter 3.45 μm and length 4.63 μm. The monolayer structure is characterized using small-angle light scattering and bright-field microscopy. With increasing field strength from 26.7 to 200 V(RMS)/cm, a transition from a disordered monolayer, to first orientationally ordered, and then translationally ordered two-dimensional (2D) arrays occurs. A c2mm plane group symmetry dominates the ordered structure but is present alongside structures with p2 symmetry, leading to a spread in the angular distribution of the light scattering peaks. The order-disorder transition dependence on field strength and frequency is similar to that observed for colloidal spheres; at higher frequencies, stronger fields are required to assemble particles. Optimal ordered structures reflect a balance between inducing sufficiently strong interparticle interactions while limiting the rate of formation to ensure the growth of large crystalline domains.
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Affiliation(s)
- Mark M Panczyk
- Department of Chemical and Biomolecular Engineering and Center for Molecular and Engineering Thermodynamics, Allan P. Colburn Laboratory, 150 Academy Street, University of Delaware, Newark, Delaware 19716, United States
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33
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Hannah DC, Ithurria S, Krylova G, Talapin DV, Schatz GC, Schaller RD. Particle-level engineering of thermal conductivity in matrix-embedded semiconductor nanocrystals. NANO LETTERS 2012; 12:5797-5801. [PMID: 23066718 DOI: 10.1021/nl303109r] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Known manipulations of semiconductor thermal transport properties rely upon higher-order material organization. Here, using time-resolved optical signatures of phonon transport, we demonstrate a "bottom-up" means of controlling thermal outflow in matrix-embedded semiconductor nanocrystals. Growth of an electronically noninteracting ZnS shell on a CdSe core modifies thermalization times by an amount proportional to the overall particle radius. Using this approach, we obtain changes in effective thermal conductivity of up to 5× for a nearly constant energy gap.
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Affiliation(s)
- Daniel C Hannah
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA
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34
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Born P, Munoz A, Cavelius C, Kraus T. Crystallization mechanisms in convective particle assembly. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:8300-8308. [PMID: 22559295 DOI: 10.1021/la2048618] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Colloidal particles are continuously assembled into crystalline particle coatings using convective fluid flows. Assembly takes place inside a meniscus on a wetting reservoir. The shape of the meniscus defines the profile of the convective flow and the motion of the particles. We use optical interference microscopy, particle image velocimetry, and particle tracking to analyze the particles' trajectory from the liquid reservoir to the film growth front and inside the deposited film as a function of temperature. Our results indicate a transition from assembly at a static film growth front at high deposition temperatures to assembly in a precursor film with high particle mobility at low deposition temperatures. A simple model that compares the convective drag on the particles to the thermal agitation explains this behavior. Convective assembly mechanisms exhibit a pronounced temperature dependency and require a temperature that provides sufficient evaporation. Capillary mechanisms are nearly temperature independent and govern assembly at lower temperatures. The model fits the experimental data with temperature and particle size as variable parameters and allows prediction of the transition temperatures. While the two mechanisms are markedly different, dried particle films from both assembly regimes exhibit hexagonal particle packings. We show that films assembled by convective mechanisms exhibit greater regularity than those assembled by capillary mechanisms.
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Affiliation(s)
- Philip Born
- Structure Formation Group, INM-Leibniz-Institute for New Materials, Saarbrücken, Germany
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35
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Yin J, Retsch M, Thomas EL, Boyce MC. Collective mechanical behavior of multilayer colloidal arrays of hollow nanoparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:5580-5588. [PMID: 22416999 DOI: 10.1021/la300039v] [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
The collective mechanical behavior of multilayer colloidal arrays of hollow silica nanoparticles (HSNP) is explored under spherical nanoindentation through a combination of experimental, numerical, and theoretical approaches. The effective indentation modulus E(ind) is found to decrease with an increasing number of layers in a nonlinear manner. The indentation force versus penetration depth behavior for multilayer hollow particle arrays is predicted by an approximate analytical model based on the spring stiffness of the individual particles and the multipoint, multiparticle interactions as well as force transmission between the layers. The model is in good agreement with experiments and with detailed finite element simulations. The ability to tune the effective indentation modulus, E(ind), of the multilayer arrays by manipulating particle geometry and layering is revealed through the model, where E(ind) = (0.725m(-3/2) + 0.275)E(mon) and E(mon) is the monolayer modulus and m is number of layers. E(ind) is seen to plateau with increasing m to E(ind_plateau) = 0.275E(mon) and E(mon) scales with (t/R)(2), t being the particle shell thickness and R being the particle radius. The scaling law governing the nonlinear decrease in indentation modulus with an increase in layer number (E(ind) scaling with m(-3/2)) is found to be similar to that governing the indentation modulus of thin solid films E(ind_solid) on a stiff substrate (where E(ind_solid) scales with h(-1.4) and also decreases until reaching a plateau value) which also decreases with an increase in film thickness h. However, the mechanisms underlying this trend for the colloidal array are clearly different, where discrete particle-to-particle interactions govern the colloidal array behavior in contrast to the substrate constraint on deformation, which governs the thickness dependence of the continuous thin film indentation modulus.
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Affiliation(s)
- Jie Yin
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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36
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Merkel A, Tournat V, Gusev V. Experimental evidence of rotational elastic waves in granular phononic crystals. PHYSICAL REVIEW LETTERS 2011; 107:225502. [PMID: 22182032 DOI: 10.1103/physrevlett.107.225502] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Indexed: 05/31/2023]
Abstract
A generalized theory of elasticity, taking into account the rotational degrees of freedom of point bodies constituting a continuum, was proposed at the beginning of the twentieth century by the Cosserat brothers. We report the experimental observation of coupled rotational-translational modes in a noncohesive granular phononic crystal. While absent in the classical theory of elasticity, these elastic wave modes are predicted by the Cosserat theory. However the Cosserat theory fails to predict correctly the dispersion of the elastic modes in granular crystals even in the long-wavelength limit.
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Affiliation(s)
- A Merkel
- LAUM, CNRS, Université du Maine, Av. O. Messiaen, 72085 Le Mans, France.
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37
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Elford DP, Chalmers L, Kusmartsev FV, Swallowe GM. Matryoshka locally resonant sonic crystal. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2011; 130:2746-55. [PMID: 22087903 DOI: 10.1121/1.3643818] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The results of numerical modeling of sonic crystals with resonant array elements are reported. The investigated resonant elements include plain slotted cylinders as well as their various combinations, in particular, Russian doll or Matryoshka configurations. The acoustic band structure and transmission characteristics of such systems have been computed with the use of finite element methods. The general concept of a locally resonant sonic crystal is proposed that utilizes acoustic resonances to form additional band gaps that are decoupled from Bragg gaps. An existence of a separate attenuation mechanism associated with the resonant elements that increases performance in the lower frequency regime has been identified. The results show a formation of broad band gaps positioned significantly below the first Bragg frequency. For low frequency broadband attenuation, a most optimal configuration is the Matryoshka sonic crystal, where each scattering unit is composed of multiple concentric slotted cylinders. This system forms numerous gaps in the lower frequency regime, below Bragg bands, while maintaining a reduced crystal size viable for noise barrier technology. The finding opens alternative perspectives for the construction of sound barriers in the low frequency range usually inaccessible by traditional means including conventional sonic crystals.
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Affiliation(s)
- Daniel P Elford
- Department of Physics, Loughborough University, Loughborough, LE11 3TU, United Kingdom.
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38
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Manzke A, Vogel N, Weiss CK, Ziener U, Plettl A, Landfester K, Ziemann P. Arrays of size and distance controlled platinum nanoparticles fabricated by a colloidal method. NANOSCALE 2011; 3:2523-8. [PMID: 21552579 DOI: 10.1039/c1nr10169b] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Based on emulsion polymerization in the presence of a Pt complex, polystyrene (PS) particles were prepared exhibiting a well defined average diameter with narrow size-distribution. Furthermore, the colloids contain a controlled concentration of the Pt precursor complex. Optimized coating of Si substrates with such colloids leads to extended areas of hexagonally ordered close-packed PS particles. Subsequent application of plasma etching and annealing steps allows complete removal of the PS carriers and in parallel nucleation and growth of Pt nanoparticles (NPs) which are located at the original center of the PS colloids. In this way, hexagonally arranged spherical Pt NPs are obtained with controlled size and interparticle distances demonstrating variability and precision with so far unknown parameter scalability. This control is demonstrated by the fabrication of Pt NP arrays at a fixed particle distance of 185 nm while systematically varying the diameters between 8 and 15 nm. Further progress could be achieved by seeded emulsion polymerization. Here, Pt loaded PS colloids of 130 nm were used as seeds for a subsequent additional emulsion polymerization, systematically enlarging the diameter of the PS particles. Applying the plasma and annealing steps as above, in this way hexagonally ordered arrays of 9 nm Pt NPs could be obtained at distances up to 260 nm. To demonstrate their stability, such Pt particles were used as etching masks during reactive ion etching thereby transferring their hexagonal pattern into the Si substrate resulting in corresponding arrays of nanopillars.
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Affiliation(s)
- Achim Manzke
- Institute of Solid State Physics, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
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39
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Still T, Gantzounis G, Kiefer D, Hellmann G, Sainidou R, Fytas G, Stefanou N. Collective hypersonic excitations in strongly multiple scattering colloids. PHYSICAL REVIEW LETTERS 2011; 106:175505. [PMID: 21635048 DOI: 10.1103/physrevlett.106.175505] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Revised: 12/15/2010] [Indexed: 05/30/2023]
Abstract
Unprecedented low-dispersion high-frequency acoustic excitations are observed in dense suspensions of elastically hard colloids. The experimental phononic band structure for SiO(2) particles with different sizes and volume fractions is well represented by rigorous full-elastodynamic multiple-scattering calculations. The slow phonons, which do not relate to particle resonances, are localized in the surrounding liquid medium and stem from coherent multiple scattering that becomes strong in the close-packing regime. Such rich phonon-matter interactions in nanostructures, being still unexplored, can open new opportunities in phononics.
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Affiliation(s)
- T Still
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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40
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Sato A, Pennec Y, Shingne N, Thurn-Albrecht T, Knoll W, Steinhart M, Djafari-Rouhani B, Fytas G. Tuning and switching the hypersonic phononic properties of elastic impedance contrast nanocomposites. ACS NANO 2010; 4:3471-3481. [PMID: 20509665 DOI: 10.1021/nn100519h] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Anodic aluminum oxide (AAO) containing arrays of aligned cylindrical nanopores infiltrated with polymers is a well-defined model system for the study of hypersound propagation in polymer nanocomposites. Hypersonic phononic properties of AAO/polymer nanocomposites such as phonon localization and anisotropic sound propagation can be tailored by adjusting elastic contrast and density contrast between the components. Changes in density and elastic properties of the component located in the nanopores induced by phase transitions allow reversible modification of the phononic band structure and mode switching. As example in case, the crystallization and melting of poly(vinylidene difluoride) inside AAO was investigated.
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Affiliation(s)
- Akihiro Sato
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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41
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Fornleitner J, Kahl G, Likos CN. Tailoring the phonon band structure in binary colloidal mixtures. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2010; 81:060401. [PMID: 20866368 DOI: 10.1103/physreve.81.060401] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Indexed: 05/29/2023]
Abstract
We analyze the phonon spectra of periodic structures formed by two-dimensional mixtures of dipolar colloidal particles. These mixtures display an enormous variety of complex ordered configurations [J. Fornleitner, Soft Matter 4, 480 (2008)], allowing for the systematic investigation of the ensuing phonon spectra and the control of phononic gaps. We show how the shape of the phonon bands and the number and width of the phonon gaps can be controlled by changing the susceptibility ratio, the composition, and the mass ratio between the two components.
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Affiliation(s)
- Julia Fornleitner
- Center for Computational Materials Science and Institut für Theoretische Physik, Technische Universität Wien, Wiedner Hauptstraße 8-10, A-1040 Vienna, Austria
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42
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Devaud M, Hocquet T, Leroy V. Sound propagation in a monodisperse bubble cloud: from the crystal to the glass. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2010; 32:13-23. [PMID: 20490600 DOI: 10.1140/epje/i2010-10588-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Revised: 03/19/2010] [Accepted: 04/09/2010] [Indexed: 05/27/2023]
Abstract
We present a theoretical study of the propagation of a monochromatic pressure wave in an unbounded monodisperse bubbly liquid. We begin with the case of a regular bubble array--a bubble crystal--for which we derive a dispersion relation. In order to interpret the different branches of this relation, we introduce a formalism, the radiative picture, which is the adaptation to acoustics of the standard splitting of the electric field in an electrostatic and a radiative part in Coulomb gauge. In the case of an irregular or completely random array--a bubble glass--and at wavelengths large compared to the size of the bubble array spatial inhomogeneities, the difference between order and disorder is not felt by the pressure wave: a dispersion relation still holds, coinciding with that of a bubble crystal with the same bubble size and air volume fraction at the centre of its first Brillouin zone. This relation is discussed and compared to that obtained by Foldy in the framework of his multiscattering approach.
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Affiliation(s)
- M Devaud
- Laboratoire Matière et Systèmes Complexes, UMR 7057, CNRS, et Université Paris Diderot, 10 rue Alice Domon et Léonie Duquet, 75205 Paris Cedex 13, France.
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43
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Salasyuk AS, Scherbakov AV, Yakovlev DR, Akimov AV, Kaplyanskii AA, Kaplan SF, Grudinkin SA, Nashchekin AV, Pevtsov AB, Golubev VG, Berstermann T, Brüggemann C, Bombeck M, Bayer M. Filtering of elastic waves by opal-based hypersonic crystal. NANO LETTERS 2010; 10:1319-1323. [PMID: 20232893 DOI: 10.1021/nl904126m] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We report experiments in which high quality silica opal films are used as three-dimensional hypersonic crystals in the 10 GHz range. Controlled sintering of these structures leads to well-defined elastic bonding between the submicrometer-sized silica spheres, due to which a band structure for elastic waves is formed. The sonic crystal properties are studied by injection of a broadband elastic wave packet with a femtosecond laser. Depending on the elastic bonding strength, the band structure separates long-living surface acoustic waves with frequencies in the complete band gap from bulk waves with band frequencies that propagate into the crystal leading to a fast decay.
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Affiliation(s)
- Alexey S Salasyuk
- Ioffe Physical-Technical Institute of the Russian Academy of Sciences, St. Petersburg, Russia
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44
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Gomopoulos N, Maschke D, Koh CY, Thomas EL, Tremel W, Butt HJ, Fytas G. One-dimensional hypersonic phononic crystals. NANO LETTERS 2010; 10:980-4. [PMID: 20141118 DOI: 10.1021/nl903959r] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We report experimental observation of a normal incidence phononic band gap in one-dimensional periodic (SiO(2)/poly(methyl methacrylate)) multilayer film at gigahertz frequencies using Brillouin spectroscopy. The band gap to midgap ratio of 0.30 occurs for elastic wave propagation along the periodicity direction, whereas for inplane propagation the system displays an effective medium behavior. The phononic properties are well captured by numerical simulations. The porosity in the silica layers presents a structural scaffold for the introduction of secondary active media for potential coupling between phonons and other excitations, such as photons and electrons.
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Affiliation(s)
- N Gomopoulos
- Max-Planck-Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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45
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Sato A, Knoll W, Pennec Y, Djafari-Rouhani B, Fytas G, Steinhart M. Anisotropic propagation and confinement of high frequency phonons in nanocomposites. J Chem Phys 2009; 130:111102. [DOI: 10.1063/1.3096972] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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46
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Still T, Sainidou R, Retsch M, Jonas U, Spahn P, Hellmann GP, Fytas G. The "music" of core-shell spheres and hollow capsules: influence of the architecture on the mechanical properties at the nanoscale. NANO LETTERS 2008; 8:3194-9. [PMID: 18767884 DOI: 10.1021/nl801500n] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We report on the first measurement of elastic vibrational modes in core-shell spheres (silica-poly(methyl methacrylate), SiO2-PMMA) and corresponding spherical hollow capsules (PMMA) with different particle size and shell thickness using Brillouin light scattering, supported by numerical calculations. These localized modes allow access to the mechanical moduli down to a few tens of nanometers. We observe reduced mechanical strength of the porous silica core, and for the core-shell spheres a striking increase of the moduli in both the SiO2 core and the PMMA shell. The peculiar behavior of the vibrational modes in the hollow capsules is attributed to antagonistic dependence on overall size and layer thickness in agreement with theoretical predictions.
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Affiliation(s)
- T Still
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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47
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Hepplestone SP, Srivastava GP. Hypersonic modes in nanophononic semiconductors. PHYSICAL REVIEW LETTERS 2008; 101:105502. [PMID: 18851224 DOI: 10.1103/physrevlett.101.105502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2008] [Indexed: 05/26/2023]
Abstract
Frequency gaps and negative group velocities of hypersonic phonon modes in periodically arranged composite semiconductors are presented. Trends and criteria for phononic gaps are discussed using a variety of atomic-level theoretical approaches. From our calculations, the possibility of achieving semiconductor-based one-dimensional phononic structures is established. We present results of the location and size of gaps, as well as negative group velocities of phonon modes in such structures. In addition to reproducing the results of recent measurements of the locations of the band gaps in the nanosized Si/Si{0.4}Ge{0.6} superlattice, we show that such a system is a true one-dimensional hypersonic phononic crystal.
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Affiliation(s)
- S P Hepplestone
- School of Physics, University of Exeter, Exeter EX4 4QL, United Kingdom
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48
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Akimov AV, Tanaka Y, Pevtsov AB, Kaplan SF, Golubev VG, Tamura S, Yakovlev DR, Bayer M. Hypersonic modulation of light in three-dimensional photonic and phononic band-gap materials. PHYSICAL REVIEW LETTERS 2008; 101:033902. [PMID: 18764257 DOI: 10.1103/physrevlett.101.033902] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Revised: 05/13/2008] [Indexed: 05/09/2023]
Abstract
The elastic coupling between the a-SiO2 spheres composing opal films brings forth three-dimensional periodic structures which besides a photonic stop band are predicted to also exhibit complete phononic band gaps. The influence of elastic crystal vibrations on the photonic band structure has been studied by injection of coherent hypersonic wave packets generated in a metal transducer by subpicosecond laser pulses. These studies show that light with energies close to the photonic band gap can be efficiently modulated by hypersonic waves.
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Affiliation(s)
- A V Akimov
- A. F. Ioffe Physical-Technical Institute, St. Petersburg, 194021 Russia
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