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Hu JD, Wang T, Lei QL, Ma YQ. Transformable Superisostatic Crystals Self-Assembled from Segment Colloidal Rods. ACS NANO 2024; 18:8073-8082. [PMID: 38456633 DOI: 10.1021/acsnano.3c11538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/09/2024]
Abstract
Transformable mechanical structures can switch between distinct mechanical states. Whether this kind of structure can be self-assembled from simple building blocks at microscale is a question to be answered. In this work, we propose a self-assembly strategy for these structures based on a nematic monolayer of segmented colloidal rods with lateral cutting. By using Monte Carlo simulation, we find that rods with different cutting degrees can self-assemble into different crystals characterized by bond coordination z that varies from 3 to 6. Among these, we identify a transformable superisostatic structure with pgg symmetry and redundant bonds (z = 5). We show that this structure can support either soft bulk modes or soft edge modes depending on its Poisson's ratio, which can be tuned from positive to negative through a uniform soft deformation. We also prove that the bulk soft modes are associated with states of self-stress along the direction of zero strain during uniform soft deformation. The self-assembled transformable structures may act as mechanical metamaterials with potential applications in micromechanical engineering.
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Affiliation(s)
- Ji-Dong Hu
- National Laboratory of Solid State Microstructures and Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, 210093 Nanjing, China
| | - Ting Wang
- School of Chemistry and Life Sciences, Nanjing University of Posts and Telecommunications, 210023 Nanjing, China
| | - Qun-Li Lei
- National Laboratory of Solid State Microstructures and Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, 210093 Nanjing, China
| | - Yu-Qiang Ma
- National Laboratory of Solid State Microstructures and Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, 210093 Nanjing, China
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2
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Elastic Wave Propagation of Two-Dimensional Metamaterials Composed of Auxetic Star-Shaped Honeycomb Structures. CRYSTALS 2019. [DOI: 10.3390/cryst9030121] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In this paper, the wave propagation in phononic crystal composed of auxetic star-shaped honeycomb matrix with negative Poisson’s ratio is presented. Two types of inclusions with circular and rectangular cross sections are considered and the band structures of the phononic crystals are also obtained by the finite element method. The band structure of the phononic crystal is affected significantly by the auxeticity of the star-shaped honeycomb. Some other interesting findings are also presented, such as the negative refraction and the self-collimation. The present study demonstrates the potential applications of the star-shaped honeycomb in phononic crystals, such as vibration isolation and the elastic waveguide.
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3
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Significant Carrier Extraction Enhancement at the Interface of an InN/p-GaN Heterojunction under Reverse Bias Voltage. NANOMATERIALS 2018; 8:nano8121039. [PMID: 30545138 PMCID: PMC6316791 DOI: 10.3390/nano8121039] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 12/06/2018] [Accepted: 12/10/2018] [Indexed: 11/17/2022]
Abstract
In this paper, a superior-quality InN/p-GaN interface grown using pulsed metalorganic vapor-phase epitaxy (MOVPE) is demonstrated. The InN/p-GaN heterojunction interface based on high-quality InN (electron concentration 5.19 × 1018 cm-3 and mobility 980 cm²/(V s)) showed good rectifying behavior. The heterojunction depletion region width was estimated to be 22.8 nm and showed the ability for charge carrier extraction without external electrical field (unbiased). Under reverse bias, the external quantum efficiency (EQE) in the blue spectral region (300⁻550 nm) can be enhanced significantly and exceeds unity. Avalanche and carrier multiplication phenomena were used to interpret the exclusive photoelectric features of the InN/p-GaN heterojunction behavior.
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4
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Maire J, Anufriev R, Yanagisawa R, Ramiere A, Volz S, Nomura M. Heat conduction tuning by wave nature of phonons. SCIENCE ADVANCES 2017; 3:e1700027. [PMID: 28798956 PMCID: PMC5544400 DOI: 10.1126/sciadv.1700027] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 06/29/2017] [Indexed: 05/02/2023]
Abstract
The world communicates to our senses of vision, hearing, and touch in the language of waves, because light, sound, and even heat essentially consist of microscopic vibrations of different media. The wave nature of light and sound has been extensively investigated over the past century and is now widely used in modern technology. However, the wave nature of heat has been the subject of mostly theoretical studies because its experimental demonstration, let alone practical use, remains challenging due to its extremely short wavelengths. We show a possibility to use the wave nature of heat for thermal conductivity tuning via spatial short-range order in phononic crystal nanostructures. Our experimental and theoretical results suggest that interference of thermal phonons occurs in strictly periodic nanostructures and slows the propagation of heat. This finding expands the methodology of heat transfer engineering to the wave nature of heat.
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Affiliation(s)
- Jeremie Maire
- Institute of Industrial Science, University of Tokyo, Tokyo 153-8505, Japan
- Laboratory for Integrated Micro Mechatronic Systems/National Center for Scientific Research–Institute of Industrial Science, University of Tokyo, Tokyo 153-8505, Japan
- Corresponding author. (M.N.); (J.M.)
| | - Roman Anufriev
- Institute of Industrial Science, University of Tokyo, Tokyo 153-8505, Japan
| | - Ryoto Yanagisawa
- Institute of Industrial Science, University of Tokyo, Tokyo 153-8505, Japan
| | - Aymeric Ramiere
- Institute of Industrial Science, University of Tokyo, Tokyo 153-8505, Japan
- Laboratory for Integrated Micro Mechatronic Systems/National Center for Scientific Research–Institute of Industrial Science, University of Tokyo, Tokyo 153-8505, Japan
| | - Sebastian Volz
- Laboratoire d’Energétique Moléculaire et Macroscopique, Combustion, UPR CNRS 288, Ecole Centrale Paris, Grande Voie des Vignes, F-92295 Châtenay-Malabry, France
| | - Masahiro Nomura
- Institute of Industrial Science, University of Tokyo, Tokyo 153-8505, Japan
- Institute for Nano Quantum Information Electronics, University of Tokyo, Tokyo 153-8505, Japan
- PRESTO, Japan Science and Technology Agency, Saitama 332-0012, Japan
- Corresponding author. (M.N.); (J.M.)
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5
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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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6
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Maldovan M. Phonon wave interference and thermal bandgap materials. NATURE MATERIALS 2015; 14:667-74. [PMID: 26099716 DOI: 10.1038/nmat4308] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 04/24/2015] [Indexed: 05/25/2023]
Abstract
Wave interference modifies phonon velocities and density of states, and in doing so creates forbidden energy bandgaps for thermal phonons. Materials that exhibit wave interference effects allow the flow of thermal energy to be manipulated by controlling the material's thermal conductivity or using heat mirrors to reflect thermal vibrations. The technological potential of these materials, such as enhanced thermoelectric energy conversion and improved thermal insulation, has fuelled the search for highly efficient phonon wave interference and thermal bandgap materials. In this Progress Article, we discuss recent developments in the understanding and manipulation of heat transport. We show that the rational design and fabrication of nanostructures provides unprecedented opportunities for creating wave-like behaviour of heat, leading to a fundamentally new approach for manipulating the transfer of thermal energy.
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Affiliation(s)
- Martin Maldovan
- 1] School of Chemical &Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA [2] School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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7
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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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8
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Lee JH, Koh CY, Singer JP, Jeon SJ, Maldovan M, Stein O, Thomas EL. 25th anniversary article: ordered polymer structures for the engineering of photons and phonons. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2014; 26:532-69. [PMID: 24338738 PMCID: PMC4227607 DOI: 10.1002/adma.201303456] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Indexed: 05/21/2023]
Abstract
The engineering of optical and acoustic material functionalities via construction of ordered local and global architectures on various length scales commensurate with and well below the characteristic length scales of photons and phonons in the material is an indispensable and powerful means to develop novel materials. In the current mature status of photonics, polymers hold a pivotal role in various application areas such as light-emission, sensing, energy, and displays, with exclusive advantages despite their relatively low dielectric constants. Moreover, in the nascent field of phononics, polymers are expected to be a superior material platform due to the ability for readily fabricated complex polymer structures possessing a wide range of mechanical behaviors, complete phononic bandgaps, and resonant architectures. In this review, polymer-centric photonic and phononic crystals and metamaterials are highlighted, and basic concepts, fabrication techniques, selected functional polymers, applications, and emerging ideas are introduced.
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Affiliation(s)
- Jae-Hwang Lee
- Department of Materials Science and Nanoengineering Rice UniversityHouston, TX, 77005, USA E-mail: ;
| | | | - Jonathan P Singer
- Department of Materials Science and Engineering, MITCambridge, MA, 02139, USA
| | - Seog-Jin Jeon
- Department of Materials Science and Nanoengineering Rice UniversityHouston, TX, 77005, USA E-mail: ;
| | - Martin Maldovan
- Department of Materials Science and Engineering, MITCambridge, MA, 02139, USA
| | - Ori Stein
- Department of Materials Science and Nanoengineering Rice UniversityHouston, TX, 77005, USA E-mail: ;
| | - Edwin L Thomas
- Department of Materials Science and Nanoengineering Rice UniversityHouston, TX, 77005, USA E-mail: ;
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9
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Maldovan M. Sound and heat revolutions in phononics. Nature 2013; 503:209-17. [PMID: 24226887 DOI: 10.1038/nature12608] [Citation(s) in RCA: 301] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 08/28/2013] [Indexed: 11/09/2022]
Abstract
The phonon is the physical particle representing mechanical vibration and is responsible for the transmission of everyday sound and heat. Understanding and controlling the phononic properties of materials provides opportunities to thermally insulate buildings, reduce environmental noise, transform waste heat into electricity and develop earthquake protection. Here I review recent progress and the development of new ideas and devices that make use of phononic properties to control both sound and heat. Advances in sonic and thermal diodes, optomechanical crystals, acoustic and thermal cloaking, hypersonic phononic crystals, thermoelectrics, and thermocrystals herald the next technological revolution in phononics.
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Affiliation(s)
- Martin Maldovan
- 1] Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA [2] School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, North Avenue, Atlanta, Georgia 30332, USA
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10
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Guo L, Marthaler M, Schön G. Phase space crystals: a new way to create a quasienergy band structure. PHYSICAL REVIEW LETTERS 2013; 111:205303. [PMID: 24289695 DOI: 10.1103/physrevlett.111.205303] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Indexed: 06/02/2023]
Abstract
A novel way to create a band structure of the quasienergy spectrum for driven systems is proposed based on the discrete symmetry in phase space. The system, e.g., an ion or ultracold atom trapped in a potential, shows no spatial periodicity, but it is driven by a time-dependent field coupling highly nonlinearly to one of its degrees of freedom (e.g., ∼q(n)). The band structure in quasienergy arises as a consequence of the n-fold discrete periodicity in phase space induced by this driving field. We propose an explicit model to realize such a phase space crystal and analyze its band structure in the frame of a tight-binding approximation. The phase space crystal opens new ways to engineer energy band structures, with the added advantage that its properties can be changed in situ by tuning the driving field's parameters.
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Affiliation(s)
- Lingzhen Guo
- Institut für Theoretische Festkörperphysik, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany and Department of Physics, Beijing Normal University, Beijing 100875, China and DFG-Center for Functional Nanostructures (CFN), Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany
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11
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Goubet N, Richardi J, Albouy PA, Pileni MP. Simultaneous interfacial and precipitated supracrystals of Au nanocrystals: experiments and simulations. J Phys Chem B 2013; 117:4510-6. [PMID: 23083458 DOI: 10.1021/jp308608g] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Under solvent saturation, a precipitation of full-grown supracrystals on the one hand and the formation of well-defined supracrystalline films at the air-liquid interface on the other hand were previously observed for the first time (J. Am. Chem. Soc.2012, 134, 3714-3719). Here, these two simultaneous growth processes are studied by additional experiments and by Brownian dynamics simulations. The thickness of the supracrystalline films and the concentration of free nanocrystals within the solution are measured as a function of the nanocrystal size. The simulations show that the first process of supracrystal growth is due to a homogeneous nucleation favored by solvent-mediated ligand interactions, while the second one is explained in terms of a diffusion process caused by a decrease in the surface energy when the particles penetrate the air-liquid interface. It is also verified that the presence of thiol molecules at the air-solution interface does not hinder the formation of supracrystalline films.
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Affiliation(s)
- Nicolas Goubet
- Université Pierre et Marie Curie, UMR 7070, LM2N, 4 place Jussieu 75005 Paris, France
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12
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Lee JH, Singer JP, Thomas EL. Micro-/nanostructured mechanical metamaterials. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2012; 24:4782-4810. [PMID: 22899377 DOI: 10.1002/adma.201201644] [Citation(s) in RCA: 140] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Revised: 05/21/2012] [Indexed: 06/01/2023]
Abstract
Mechanical properties of materials have long been one of the most fundamental and studied areas of materials science for a myriad of applications. Recently, mechanical metamaterials have been shown to possess extraordinary effective properties, such as negative dynamic modulus and/or density, phononic bandgaps, superior thermoelectric properties, and high specific energy absorption. To obtain such materials on appropriate length scales to enable novel mechanical devices, it is often necessary to effectively design and fabricate micro-/nano- structured materials. In this Review, various aspects of the micro-/nano-structured materials as mechanical metamaterials, potential tools for their multidimensional fabrication, and selected methods for their structural and performance characterization are described, as well as some prospects for the future developments in this exciting and emerging field.
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Affiliation(s)
- Jae-Hwang Lee
- Department of Mechanical Engineering and Materials Science, Rice University, 6100 Main St., Houston, Texas 77005, USA
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13
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Khalil KS, Sagastegui A, Li Y, Tahir MA, Socolar JES, Wiley BJ, Yellen BB. Binary colloidal structures assembled through Ising interactions. Nat Commun 2012; 3:794. [DOI: 10.1038/ncomms1798] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Accepted: 03/21/2012] [Indexed: 11/09/2022] Open
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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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Jang JH, Koh CY, Bertoldi K, Boyce MC, Thomas EL. Combining pattern instability and shape-memory hysteresis for phononic switching. NANO LETTERS 2009; 9:2113-2119. [PMID: 19391612 DOI: 10.1021/nl9006112] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We report a fully reversible and robust shape-memory effect in a two-dimensional nanoscale periodic structure composed of three steps, the elastic instability governing the transformation, the plasticity that locks in the transformed pattern as a result of an increase in glass transition temperature (T(g)), and the subsequent elastic recovery due to the vapor-induced decrease in T(g). Solvent swelling of a cross-linked epoxy/air cylinder structure induces an elastic instability that causes a reversible change in the shape of the void regions from circular to oval. The pattern symmetry changes from symmorphic p6mm to nonsymmorphic p2gg brought via the introduction of new glide symmetry elements and leads to a significant change in the phononic band structure, specifically in the opening of a new narrow-band gap due to anticrossing of bands, quite distinct from gaps originating from typical Bragg scattering. We also demonstrate that numerical simulations correctly capture the three steps of the shape-memory cycle observed experimentally.
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Affiliation(s)
- Ji-Hyun Jang
- Institute for Soldier Nanotechnologies, Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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16
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Zhang J, Sun Z, Yang B. Self-assembly of photonic crystals from polymer colloids. Curr Opin Colloid Interface Sci 2009. [DOI: 10.1016/j.cocis.2008.09.001] [Citation(s) in RCA: 189] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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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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18
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Baumgartl J, Zvyagolskaya M, Bechinger C. Tailoring of phononic band structures in colloidal crystals. PHYSICAL REVIEW LETTERS 2007; 99:205503. [PMID: 18233158 DOI: 10.1103/physrevlett.99.205503] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2007] [Indexed: 05/25/2023]
Abstract
We report an experimental study of the elastic properties of a two-dimensional (2D) colloidal crystal subjected to light-induced substrate potentials. In agreement with recent theoretical predictions [H. H. von Grünberg and J. Baumgartl, Phys. Rev. E 75, 051406 (2007).10.1103/PhysRevE.75.051406] the phonon band structure of such systems can be tuned depending on the symmetry and depth of the substrate potential. Calculations with binary crystals suggest that phononic band engineering can be also performed by variations of the pair potential and thus opens novel perspectives for the fabrication of phononic crystals with band gaps tunable by external fields.
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Affiliation(s)
- J Baumgartl
- Physikalisches Institut, Universität Stuttgart, 70550 Stuttgart, Germany.
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