51
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Tavakoli A, Lulla K, Crozes T, Mingo N, Collin E, Bourgeois O. Heat conduction measurements in ballistic 1D phonon waveguides indicate breakdown of the thermal conductance quantization. Nat Commun 2018; 9:4287. [PMID: 30327470 PMCID: PMC6191430 DOI: 10.1038/s41467-018-06791-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 09/21/2018] [Indexed: 11/09/2022] Open
Abstract
Emerging quantum technologies require mastering thermal management, especially at the nanoscale. It is now accepted that thermal metamaterial-based phonon manipulation is possible, especially at sub-kelvin temperatures. In these extreme limits of low temperatures and dimensions, heat conduction enters a quantum regime where phonon exchange obeys the Landauer formalism. Phonon transport is then governed by the transmission coefficients between the ballistic conductor and the thermal reservoirs. Here we report on ultra-sensitive thermal experiments made on ballistic 1D phonon conductors using a micro-platform suspended sensor. Our thermal conductance measurements attain a power sensitivity of 15 attoWatts \documentclass[12pt]{minimal}
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\begin{document}$$\sqrt {{\mathrm{Hz}}} \,^{ - 1}$$\end{document}Hz-1 around 100 mK. Ballistic thermal transport is dominated by non-ideal transmission coefficients and not by the quantized thermal conductance of the nanowire itself. This limitation of heat transport in the quantum regime may have a significant impact on modern thermal management and thermal circuit design. At low temperatures and dimensionality it has become possible to probe the quantum limits of heat transport. Tavakoli et al. show that heat transport through a one-dimensional device can be dominated by non-ideal transmission instead of reaching the regime of thermal conductance quantization.
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Affiliation(s)
- Adib Tavakoli
- Institut NÉEL, CNRS, 25 avenue des Martyrs, 38042, Grenoble, France.,Inst NEEL, Univ. Grenoble Alpes, 38042, Grenoble, France
| | - Kunal Lulla
- Institut NÉEL, CNRS, 25 avenue des Martyrs, 38042, Grenoble, France.,Inst NEEL, Univ. Grenoble Alpes, 38042, Grenoble, France
| | - Thierry Crozes
- Institut NÉEL, CNRS, 25 avenue des Martyrs, 38042, Grenoble, France.,Inst NEEL, Univ. Grenoble Alpes, 38042, Grenoble, France
| | - Natalio Mingo
- LITEN, CEA-Grenoble, 17 avenue des Martyrs, 38054, Grenoble Cedex 9, France
| | - Eddy Collin
- Institut NÉEL, CNRS, 25 avenue des Martyrs, 38042, Grenoble, France.,Inst NEEL, Univ. Grenoble Alpes, 38042, Grenoble, France
| | - Olivier Bourgeois
- Institut NÉEL, CNRS, 25 avenue des Martyrs, 38042, Grenoble, France. .,Inst NEEL, Univ. Grenoble Alpes, 38042, Grenoble, France.
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52
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Guo R, Jho YD, Minnich AJ. Coherent control of thermal phonon transport in van der Waals superlattices. NANOSCALE 2018; 10:14432-14440. [PMID: 29808882 DOI: 10.1039/c8nr02150c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
van der Waals (vdW) heterostructures are a central focus of materials science and condensed matter physics due to the novel physical phenomena and properties obtained by precisely stacking heterogeneous atomically thin layers. vdW heterostructures are expected to allow for the coherent manipulation of THz lattice vibrations and hence heat conduction due to the ability to precisely control chemical composition at the atomic scale, but little work has focused on thermal transport in these materials. Here, we report an ab initio study of thermal transport in vdW superlattices consisting of alternating transition metal dichalcogenide atomic layers. Our calculations show that the lattice vibrational spectrum and scattering rates can be precisely manipulated by the choice of each atomically thin layer, resulting in materials with novel properties such as large thermal anisotropies approaching 200 and ultralow cross-plane thermal conductivities comparable to those of amorphous materials. Our work demonstrates how coherent manipulation of phonons in vdW superlattices can expand the property space beyond that occupied by natural materials and suggests an experimental route to realize these properties.
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Affiliation(s)
- Ruiqiang Guo
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, California 91125, USA.
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53
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Krödel S, Palermo A, Daraio C. Acoustic properties of porous microlattices from effective medium to scattering dominated regimes. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2018; 144:319. [PMID: 30075686 DOI: 10.1121/1.5046068] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 06/24/2018] [Indexed: 06/08/2023]
Abstract
Microlattices are architected materials that allow for an unprecedented control of mechanical properties (e.g., stiffness, density, and Poisson's coefficient). In contrast to their quasi-static mechanical properties, the acoustic properties of microlattices remain largely unexplored. This paper analyzes the acoustic response of periodic millimeter-sized microlattices immersed in water using experiments and numerical simulations. Microlattices are fabricated using high-precision stereolithographic three-dimensional printing in a large variety of porosities and lattice topologies. This paper shows that the acoustic propagation undergoes a frequency dependent transition from a classic poroelastic behaviour that can be described by Biot's theory to a regime that is dominated by scattering effects. Biot's acoustic parameters are derived from direct simulations of the microstructure using coupled fluid and solid finite elements. The wave speeds predicted with Biot's theory agree well with the experimental measures. Within the scattering regime, the signals show a strong attenuation and dispersion, which is characterized by a cut-off frequency. The strong dispersion results in a frequency dependent group velocity. A simplified model of an elastic cylindrical scatterer allows predicting the signal attenuation and dispersion observed experimentally. The results in this paper pave the way for the creation of microlattice materials for the control of ultrasonic waves across a wide range of frequencies.
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Affiliation(s)
- Sebastian Krödel
- Department of Mechanical and Process Engineering, ETH Zürich, Tannenstrasse 3, 8092, Zürich, Switzerland
| | - Antonio Palermo
- Department of Civil, Chemical, Environmental and Materials Engineering, University of Bologna, Viale del Risorgimento 2, Bologna 40136, Italy
| | - Chiara Daraio
- Division of Engineering and Applied Science, California Institute of Technology, 1200 California Boulevard, Pasadena, California 91125, USA
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54
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Cross-plane coherent acoustic phonons in two-dimensional organic-inorganic hybrid perovskites. Nat Commun 2018; 9:2019. [PMID: 29789666 PMCID: PMC5964251 DOI: 10.1038/s41467-018-04429-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 04/17/2018] [Indexed: 11/16/2022] Open
Abstract
Two-dimensional Ruddlesden–Popper organic–inorganic hybrid layered perovskites (2D RPs) are solution-grown semiconductors with prospective applications in next-generation optoelectronics. The heat-carrying, low-energy acoustic phonons, which are important for heat management of 2D RP-based devices, have remained unexplored. Here we report on the generation and propagation of coherent longitudinal acoustic phonons along the cross-plane direction of 2D RPs, following separate characterizations of below-bandgap refractive indices. Through experiments on single crystals of systematically varied perovskite layer thickness, we demonstrate significant reduction in both group velocity and propagation length of acoustic phonons in 2D RPs as compared to the three-dimensional methylammonium lead iodide counterpart. As borne out by a minimal coarse-grained model, these vibrational properties arise from a large acoustic impedance mismatch between the alternating layers of perovskite sheets and bulky organic cations. Our results inform on thermal transport in highly impedance-mismatched crystal sub-lattices and provide insights towards design of materials that exhibit highly anisotropic thermal dissipation properties. Two-dimensional, organic-inorganic hybrid perovskites have sustained research interest due to attractive optoelectronic and excitonic properties. Here, Guo et al. systematically investigate coherent acoustic phonon transport versus layer thickness in these materials with strong acoustic impedance mismatch
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55
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Seif A, DeGottardi W, Esfarjani K, Hafezi M. Thermal management and non-reciprocal control of phonon flow via optomechanics. Nat Commun 2018; 9:1207. [PMID: 29572521 PMCID: PMC5865216 DOI: 10.1038/s41467-018-03624-y] [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: 09/12/2017] [Accepted: 02/28/2018] [Indexed: 11/09/2022] Open
Abstract
Engineering phonon transport in physical systems is a subject of interest in the study of materials, and has a crucial role in controlling energy and heat transfer. Of particular interest are non-reciprocal phononic systems, which in direct analogy to electric diodes, provide a directional flow of energy. Here, we propose an engineered nanostructured material, in which tunable non-reciprocal phonon transport is achieved through optomechanical coupling. Our scheme relies on breaking time-reversal symmetry by a spatially varying laser drive, which manipulates low-energy acoustic phonons. Furthermore, we take advantage of developments in the manipulation of high-energy phonons through controlled scattering mechanisms, such as using alloys and introducing disorder. These combined approaches allow us to design an acoustic isolator and a thermal diode. Our proposed device will have potential impact in phonon-based information processing, and heat management in low temperatures. Phonon transport control is important for thermal and non-reciprocal devices. Here, Seif et al. combine heat transport in nanostructures and optomechanics into a platform for manipulating phonons with which they design an acoustic isolator and a thermal diode.
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Affiliation(s)
- Alireza Seif
- Joint Quantum Institute, NIST/University of Maryland, College Park, MD, 20742, USA.,Department of Physics, University of Maryland, College Park, MD, 20742, USA
| | - Wade DeGottardi
- Joint Quantum Institute, NIST/University of Maryland, College Park, MD, 20742, USA.,Department of Physics, University of Maryland, College Park, MD, 20742, USA.,Department of Electrical and Computer Engineering and Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD, 20742, USA
| | - Keivan Esfarjani
- Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, VA, 22904, USA.,Departments of Materials Science and Engineering, University of Virginia, Charlottesville, VA, 22904, USA.,Department of Physics, University of Virginia, Charlottesville, VA, 22904, USA
| | - Mohammad Hafezi
- Joint Quantum Institute, NIST/University of Maryland, College Park, MD, 20742, USA. .,Department of Physics, University of Maryland, College Park, MD, 20742, USA. .,Department of Electrical and Computer Engineering and Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD, 20742, USA.
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56
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Abstract
Superlattices are ideal model systems for the realization and understanding of coherent (wave-like) and incoherent (particle-like) phonon thermal transport. Single layer heterostructures of graphene and hexagonal boron nitride have been produced recently with sharp edges and controlled domain sizes. In this study we employ nonequilibrium molecular dynamics simulations to investigate the thermal conductivity of superlattice nanoribbons with equal-sized domains of graphene and hexagonal boron nitride. We analyze the dependence of the conductivity with the domain sizes, and with the total length of the ribbons. We determine that the thermal conductivity reaches a minimum value of 89 W m−1K−1 for ribbons with a superlattice period of 3.43 nm. The effective phonon mean free path is also determined and shows a minimum value of 32 nm for the same superlattice period. Our results also reveal that a crossover from coherent to incoherent phonon transport is present at room temperature for BNC nanoribbons, as the superlattice period becomes comparable to the phonon coherence length. Analyzing phonon populations relative to the smallest superlattice period, we attribute the minimum thermal conductivity to a reduction in the population of flexural phonons when the superlattice period equals 3.43 nm. The ability to manipulate thermal conductivity using superlattice-based two-dimensional materials, such as graphene-hBN nanoribbons, opens up opportunities for application in future nanostructured thermoelectric devices.
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57
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Malhotra A, Kothari K, Maldovan M. Enhancing Thermal Transport in Layered Nanomaterials. Sci Rep 2018; 8:1880. [PMID: 29382869 PMCID: PMC5789832 DOI: 10.1038/s41598-018-20183-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 01/10/2018] [Indexed: 11/09/2022] Open
Abstract
A comprehensive rational thermal material design paradigm requires the ability to reduce and enhance the thermal conductivities of nanomaterials. In contrast to the existing ability to reduce the thermal conductivity, methods that allow to enhance heat conduction are currently limited. Enhancing the nanoscale thermal conductivity could bring radical improvements in the performance of electronics, optoelectronics, and photovoltaic systems. Here, we show that enhanced thermal conductivities can be achieved in semiconductor nanostructures by rationally engineering phonon spectral coupling between materials. By embedding a germanium film between silicon layers, we show that its thermal conductivity can be increased by more than 100% at room temperature in contrast to a free standing thin-film. The injection of phonons from the cladding silicon layers creates the observed enhancement in thermal conductivity. We study the key factors underlying the phonon injection mechanism and find that the surface conditions and layer thicknesses play a determining role. The findings presented here will allow for the creation of nanomaterials with an increased thermal conductivity.
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Affiliation(s)
- Abhinav Malhotra
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Kartik Kothari
- School of Physics, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Martin Maldovan
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA. .,School of Physics, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
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58
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Nakamura Y. Nanostructure design for drastic reduction of thermal conductivity while preserving high electrical conductivity. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2018; 19:31-43. [PMID: 29371907 PMCID: PMC5769778 DOI: 10.1080/14686996.2017.1413918] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 12/02/2017] [Accepted: 12/02/2017] [Indexed: 05/11/2023]
Abstract
The design and fabrication of nanostructured materials to control both thermal and electrical properties are demonstrated for high-performance thermoelectric conversion. We have focused on silicon (Si) because it is an environmentally friendly and ubiquitous element. High bulk thermal conductivity of Si limits its potential as a thermoelectric material. The thermal conductivity of Si has been reduced by introducing grains, or wires, yet a further reduction is required while retaining a high electrical conductivity. We have designed two different nanostructures for this purpose. One structure is connected Si nanodots (NDs) with the same crystal orientation. The phonons scattering at the interfaces of these NDs occurred and it depended on the ND size. As a result of phonon scattering, the thermal conductivity of this nanostructured material was below/close to the amorphous limit. The other structure is Si films containing epitaxially grown Ge NDs. The Si layer imparted high electrical conductivity, while the Ge NDs served as phonon scattering bodies reducing thermal conductivity drastically. This work gives a methodology for the independent control of electron and phonon transport using nanostructured materials. This can bring the realization of thermoelectric Si-based materials that are compatible with large scale integrated circuit processing technologies.
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Affiliation(s)
- Yoshiaki Nakamura
- Graduate School of Engineering Science, Osaka University, Toyonaka, Japan
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59
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Thermal conductivity and air-mediated losses in periodic porous silicon membranes at high temperatures. Nat Commun 2017; 8:415. [PMID: 28871197 PMCID: PMC5583326 DOI: 10.1038/s41467-017-00115-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 06/02/2017] [Indexed: 11/08/2022] Open
Abstract
Heat conduction in silicon can be effectively engineered by means of sub-micrometre porous thin free-standing membranes. Tunable thermal properties make these structures good candidates for integrated heat management units such as waste heat recovery, rectification or efficient heat dissipation. However, possible applications require detailed thermal characterisation at high temperatures which, up to now, has been an experimental challenge. In this work we use the contactless two-laser Raman thermometry to study heat dissipation in periodic porous membranes at high temperatures via lattice conduction and air-mediated losses. We find the reduction of the thermal conductivity and its temperature dependence closely correlated with the structure feature size. On the basis of two-phonon Raman spectra, we attribute this behaviour to diffuse (incoherent) phonon-boundary scattering. Furthermore, we investigate and quantify the heat dissipation via natural air-mediated cooling, which can be tuned by engineering the porosity.Nanostructuring of silicon allows acoustic phonon engineering, but the mechanism of related thermal transport in these structures is not fully understood. Here, the authors study the heat dissipation in silicon membranes with periodic nanoholes and show the importance of incoherent scattering.
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60
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Manfrinato VR, Stein A, Zhang L, Nam CY, Yager KG, Stach EA, Black CT. Aberration-Corrected Electron Beam Lithography at the One Nanometer Length Scale. NANO LETTERS 2017; 17:4562-4567. [PMID: 28418673 DOI: 10.1021/acs.nanolett.7b00514] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Patterning materials efficiently at the smallest length scales is a longstanding challenge in nanotechnology. Electron-beam lithography (EBL) is the primary method for patterning arbitrary features, but EBL has not reliably provided sub-4 nm patterns. The few competing techniques that have achieved this resolution are orders of magnitude slower than EBL. In this work, we employed an aberration-corrected scanning transmission electron microscope for lithography to achieve unprecedented resolution. Here we show aberration-corrected EBL at the one nanometer length scale using poly(methyl methacrylate) (PMMA) and have produced both the smallest isolated feature in any conventional resist (1.7 ± 0.5 nm) and the highest density patterns in PMMA (10.7 nm pitch for negative-tone and 17.5 nm pitch for positive-tone PMMA). We also demonstrate pattern transfer from the resist to semiconductor and metallic materials at the sub-5 nm scale. These results indicate that polymer-based nanofabrication can achieve feature sizes comparable to the Kuhn length of PMMA and ten times smaller than its radius of gyration. Use of aberration-corrected EBL will increase the resolution, speed, and complexity in nanomaterial fabrication.
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Affiliation(s)
- Vitor R Manfrinato
- Center for Functional Nanomaterials, Brookhaven National Laboratory , Upton, New York 11973-5000, United States
| | - Aaron Stein
- Center for Functional Nanomaterials, Brookhaven National Laboratory , Upton, New York 11973-5000, United States
| | - Lihua Zhang
- Center for Functional Nanomaterials, Brookhaven National Laboratory , Upton, New York 11973-5000, United States
| | - Chang-Yong Nam
- Center for Functional Nanomaterials, Brookhaven National Laboratory , Upton, New York 11973-5000, United States
| | - Kevin G Yager
- Center for Functional Nanomaterials, Brookhaven National Laboratory , Upton, New York 11973-5000, United States
| | - Eric A Stach
- Center for Functional Nanomaterials, Brookhaven National Laboratory , Upton, New York 11973-5000, United States
| | - Charles T Black
- Center for Functional Nanomaterials, Brookhaven National Laboratory , Upton, New York 11973-5000, United States
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61
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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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62
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Phonon Surface Scattering and Thermal Energy Distribution in Superlattices. Sci Rep 2017; 7:5625. [PMID: 28717137 PMCID: PMC5514034 DOI: 10.1038/s41598-017-05631-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 05/31/2017] [Indexed: 11/08/2022] Open
Abstract
Thermal transport at small length scales has attracted significant attention in recent years and various experimental and theoretical methods have been developed to establish the reduced thermal conductivity. The fundamental understanding of how phonons move and the physical mechanisms behind nanoscale thermal transport, however, remains poorly understood. Here we move beyond thermal conductivity calculations and provide a rigorous and comprehensive physical description of thermal phonon transport in superlattices by solving the Boltzmann transport equation and using the Beckman-Kirchhoff surface scattering theory with shadowing to precisely describe phonon-surface interactions. We show that thermal transport in superlattices can be divided in two different heat transport modes having different physical properties at small length scales: layer-restricted and extended heat modes. We study how interface conditions, periodicity, and composition can be used to manipulate the distribution of thermal energy flow among such layer-restricted and extended heat modes. From predicted frequency and mean free path spectra of superlattices, we also investigate the existence of wave effects. The results and insights in this paper advance the fundamental understanding of heat transport in superlattices and the prospects of rationally designing thermal systems with tailored phonon transport properties.
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63
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Anufriev R, Ramiere A, Maire J, Nomura M. Heat guiding and focusing using ballistic phonon transport in phononic nanostructures. Nat Commun 2017; 8:15505. [PMID: 28516909 PMCID: PMC5454390 DOI: 10.1038/ncomms15505] [Citation(s) in RCA: 107] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 04/03/2017] [Indexed: 12/20/2022] Open
Abstract
Unlike classical heat diffusion at macroscale, nanoscale heat conduction can occur without energy dissipation because phonons can ballistically travel in straight lines for hundreds of nanometres. Nevertheless, despite recent experimental evidence of such ballistic phonon transport, control over its directionality, and thus its practical use, remains a challenge, as the directions of individual phonons are chaotic. Here, we show a method to control the directionality of ballistic phonon transport using silicon membranes with arrays of holes. First, we demonstrate that the arrays of holes form fluxes of phonons oriented in the same direction. Next, we use these nanostructures as directional sources of ballistic phonons and couple the emitted phonons into nanowires. Finally, we introduce thermal lens nanostructures, in which the emitted phonons converge at the focal point, thus focusing heat into a spot of a few hundred nanometres. These results motivate the concept of ray-like heat manipulations at the nanoscale.
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Affiliation(s)
- Roman Anufriev
- Institute of Industrial Science, the University of Tokyo, Tokyo 153–8505, Japan
| | - Aymeric Ramiere
- Institute of Industrial Science, the University of Tokyo, Tokyo 153–8505, Japan
- Laboratory for Integrated Micro Mechatronic Systems/National Center for Scientific Research-Institute of Industrial Science (LIMMS/CNRS-IIS), the University of Tokyo, Tokyo 153–8505, Japan
| | - Jeremie Maire
- 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
- PRESTO, Japan Science and Technology Agency, Saitama 332–0012, Japan
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64
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Wang G, Wang C, Zhao J, Wang G, Park CB, Zhao G. Modelling of thermal transport through a nanocellular polymer foam: toward the generation of a new superinsulating material. NANOSCALE 2017; 9:5996-6009. [PMID: 28440837 DOI: 10.1039/c7nr00327g] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Superinsulating materials play a pivotal role in achieving the sustainable development of our modern world by improving energy efficiency, and reducing energy consumption and CO2 emission. Nanocellular polymer foams have been considered as a promising superinsulating material, but their development is yet to be achieved. The understanding of thermal transport through the nanocellular foam is crucial for developing this superinsulating material. Herein, we report an accurate mathematical model for the first time to quantitatively estimate thermal transport through the nanocellular polymer foam. This is realized by taking into account the phonon scattering effect, the Knudsen effect and the thin-film interference effect in modeling the thermal transport through solid conduction, gas conduction and thermal radiation, respectively. We demonstrate a quantitative relationship between the cellular structure and the equivalent thermal conductivity and present the optimum cellular structure scope for achieving the superinsulating performance. In particular, the significance of thermal radiation in the nanocellular polymer foam is emphasized. This mathematical model offers a very useful tool for deeply understanding thermal transport through the nanocellular polymer foams, and guiding the development of the new generation of superinsulating materials.
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Affiliation(s)
- Guilong Wang
- Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, School of Materials Science and Engineering, Shandong University, Jinan, Shandong 250061, China. ,
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65
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Maire J, Anufriev R, Nomura M. Ballistic thermal transport in silicon nanowires. Sci Rep 2017; 7:41794. [PMID: 28150724 PMCID: PMC5288788 DOI: 10.1038/srep41794] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 12/28/2016] [Indexed: 11/16/2022] Open
Abstract
We have experimentally investigated the impact of dimensions and temperature on the thermal conductivity of silicon nanowires fabricated using a top-down approach. Both the width and temperature dependences of thermal conductivity agree with those in the existing literature. The length dependence of thermal conductivity exhibits a transition from semi-ballistic thermal phonon transport at 4 K to fully diffusive transport at room temperature. We additionally calculated the phonon dispersion in these structures in the framework of the theory of elasticity and showed that the thermal conductance increases with width. This agrees with our experimental observations and supports the pertinence of using the modified phonon dispersion at low temperatures.
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Affiliation(s)
- Jeremie Maire
- Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan.,Laboratory for Integrated Micro Mechatronic Systems/National Center for Scientific Research-Institute of Industrial Science (LIMMS/CNRS-IIS), 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.,Institute for Nano Quantum Information Electronics, The University of Tokyo, Tokyo 153-8505, Japan.,PRESTO, Japan Science and Technology Agency, Saitama 332-0012, Japan
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66
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Lee J, Lee W, Wehmeyer G, Dhuey S, Olynick DL, Cabrini S, Dames C, Urban JJ, Yang P. Investigation of phonon coherence and backscattering using silicon nanomeshes. Nat Commun 2017; 8:14054. [PMID: 28051081 PMCID: PMC5216120 DOI: 10.1038/ncomms14054] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 11/23/2016] [Indexed: 12/20/2022] Open
Abstract
Phonons can display both wave-like and particle-like behaviour during thermal transport. While thermal transport in silicon nanomeshes has been previously interpreted by phonon wave effects due to interference with periodic structures, as well as phonon particle effects including backscattering, the dominant mechanism responsible for thermal conductivity reductions below classical predictions still remains unclear. Here we isolate the wave-related coherence effects by comparing periodic and aperiodic nanomeshes, and quantify the backscattering effect by comparing variable-pitch nanomeshes. We measure identical (within 6% uncertainty) thermal conductivities for periodic and aperiodic nanomeshes of the same average pitch, and reduced thermal conductivities for nanomeshes with smaller pitches. Ray tracing simulations support the measurement results. We conclude phonon coherence is unimportant for thermal transport in silicon nanomeshes with periodicities of 100 nm and higher and temperatures above 14 K, and phonon backscattering, as manifested in the classical size effect, is responsible for the thermal conductivity reduction.
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Affiliation(s)
- Jaeho Lee
- Department of Chemistry, University of California, Berkeley, California 94720, USA.,Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.,Department of Mechanical and Aerospace Engineering, University of California, Irvine, California 92697, USA
| | - Woochul Lee
- Department of Chemistry, University of California, Berkeley, California 94720, USA.,Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Geoff Wehmeyer
- Department of Mechanical Engineering, University of California, Berkeley, California 94720, USA
| | - Scott Dhuey
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Deirdre L Olynick
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Stefano Cabrini
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Chris Dames
- Department of Mechanical Engineering, University of California, Berkeley, California 94720, USA
| | - Jeffrey J Urban
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Peidong Yang
- Department of Chemistry, University of California, Berkeley, California 94720, USA.,Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.,Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.,Kavli Energy NanoScience Institute, Berkeley, California 94720, USA
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67
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Seiler A, Piekarz P, Ibrahimkutty S, Merkel DG, Waller O, Pradip R, Chumakov AI, Rüffer R, Baumbach T, Parlinski K, Fiederle M, Stankov S. Anomalous Lattice Dynamics of EuSi_{2} Nanoislands: Role of Interfaces Unveiled. PHYSICAL REVIEW LETTERS 2016; 117:276101. [PMID: 28084777 DOI: 10.1103/physrevlett.117.276101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Indexed: 06/06/2023]
Abstract
We report a systematic lattice dynamics study of EuSi_{2} films and nanoislands by in situ nuclear inelastic scattering on ^{151}Eu and ab initio theory. The Eu-partial phonon density of states of the nanoislands exhibits anomalous excess of phonon states at low and high energies, not present in the bulk and at the EuSi_{2}(001) surface. We demonstrate that atomic vibrations along the island-substrate interface give rise to phonon states both at low and high energies, while atomic vibrations across the island-island interface result in localized high-energy phonon modes.
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Affiliation(s)
- A Seiler
- Laboratory for Applications of Synchrotron Radiation, Karlsruhe Institute of Technology, D-76131 Karlsruhe, Germany
- Institute for Photon Science and Synchrotron Radiation, Karlsruhe Institute of Technology, D-76344 Eggenstein-Leopoldshafen, Germany
| | - P Piekarz
- Institute of Nuclear Physics, Polish Academy of Sciences, PL-31342 Kraków, Poland
| | - S Ibrahimkutty
- Laboratory for Applications of Synchrotron Radiation, Karlsruhe Institute of Technology, D-76131 Karlsruhe, Germany
- Institute for Photon Science and Synchrotron Radiation, Karlsruhe Institute of Technology, D-76344 Eggenstein-Leopoldshafen, Germany
| | - D G Merkel
- ESRF-The European Synchrotron, F-38000 Grenoble, France
| | - O Waller
- Laboratory for Applications of Synchrotron Radiation, Karlsruhe Institute of Technology, D-76131 Karlsruhe, Germany
- Institute for Photon Science and Synchrotron Radiation, Karlsruhe Institute of Technology, D-76344 Eggenstein-Leopoldshafen, Germany
| | - R Pradip
- Laboratory for Applications of Synchrotron Radiation, Karlsruhe Institute of Technology, D-76131 Karlsruhe, Germany
- Institute for Photon Science and Synchrotron Radiation, Karlsruhe Institute of Technology, D-76344 Eggenstein-Leopoldshafen, Germany
| | - A I Chumakov
- ESRF-The European Synchrotron, F-38000 Grenoble, France
| | - R Rüffer
- ESRF-The European Synchrotron, F-38000 Grenoble, France
| | - T Baumbach
- Laboratory for Applications of Synchrotron Radiation, Karlsruhe Institute of Technology, D-76131 Karlsruhe, Germany
- Institute for Photon Science and Synchrotron Radiation, Karlsruhe Institute of Technology, D-76344 Eggenstein-Leopoldshafen, Germany
- ANKA Synchrotron Radiation Facility, Karlsruhe Institute of Technology, D-76344 Eggenstein-Leopoldshafen, Germany
| | - K Parlinski
- Institute of Nuclear Physics, Polish Academy of Sciences, PL-31342 Kraków, Poland
| | - M Fiederle
- Freiburg Materials Research Center, University of Freiburg, D-79104 Freiburg, Germany
| | - S Stankov
- Laboratory for Applications of Synchrotron Radiation, Karlsruhe Institute of Technology, D-76131 Karlsruhe, Germany
- Institute for Photon Science and Synchrotron Radiation, Karlsruhe Institute of Technology, D-76344 Eggenstein-Leopoldshafen, Germany
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68
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Engineered metabarrier as shield from seismic surface waves. Sci Rep 2016; 6:39356. [PMID: 27996051 PMCID: PMC5172158 DOI: 10.1038/srep39356] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 11/22/2016] [Indexed: 11/11/2022] Open
Abstract
Resonant metamaterials have been proposed to reflect or redirect elastic waves at different length scales, ranging from thermal vibrations to seismic excitation. However, for seismic excitation, where energy is mostly carried by surface waves, energy reflection and redirection might lead to harming surrounding regions. Here, we propose a seismic metabarrier able to convert seismic Rayleigh waves into shear bulk waves that propagate away from the soil surface. The metabarrier is realized by burying sub-wavelength resonant structures under the soil surface. Each resonant structure consists of a cylindrical mass suspended by elastomeric springs within a concrete case and can be tuned to the resonance frequency of interest. The design allows controlling seismic waves with wavelengths from 10-to-100 m with meter-sized resonant structures. We develop an analytical model based on effective medium theory able to capture the mode conversion mechanism. The model is used to guide the design of metabarriers for varying soil conditions and validated using finite-element simulations. We investigate the shielding performance of a metabarrier in a scaled experimental model and demonstrate that surface ground motion can be reduced up to 50% in frequency regions below 10 Hz, relevant for the protection of buildings and civil infrastructures.
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69
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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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70
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Mante PA, Lehmann S, Anttu N, Dick KA, Yartsev A. Nondestructive Complete Mechanical Characterization of Zinc Blende and Wurtzite GaAs Nanowires Using Time-Resolved Pump-Probe Spectroscopy. NANO LETTERS 2016; 16:4792-4798. [PMID: 27352041 DOI: 10.1021/acs.nanolett.6b00786] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We have developed and demonstrated an experimental method, based on the picosecond acoustics technique, to perform nondestructive complete mechanical characterization of nanowires, that is, the determination of the complete elasticity tensor. By means of femtosecond pump-probe spectroscopy, coherent acoustic phonons were generated in an ensemble of nanowires and their dynamics was resolved. Specific phonon modes were identified and the detection mechanism was addressed via wavelength dependent experiments. We calculated the exact phonon dispersion relation of the nanowires by fitting the experimentally observed frequencies, thus allowing the extraction of the complete elasticity tensor. The elasticity tensor and the nanowire diameter were determined for zinc blende GaAs nanowires and were found to be in a good agreement with literature data and independent measurements. Finally, we have applied this technique to characterize wurtzite GaAs nanowires, a metastable phase in bulk, for which no experimental values of elastic constants are currently available. Our results agree well with previous first principle calculations. The proposed approach to the complete and nondestructive mechanical characterization of nanowires will allow the efficient mechanical study of new crystal phases emerging in nanostructures, as well as size-dependent properties of nanostructured materials.
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Affiliation(s)
- Pierre-Adrien Mante
- Department of Chemical Physics, ‡NanoLund, §Department of Solid State Physics, and ∥Center for Analysis and Synthesis, Lund University , S-221 00 Lund, Sweden
| | - Sebastian Lehmann
- Department of Chemical Physics, ‡NanoLund, §Department of Solid State Physics, and ∥Center for Analysis and Synthesis, Lund University , S-221 00 Lund, Sweden
| | - Nicklas Anttu
- Department of Chemical Physics, ‡NanoLund, §Department of Solid State Physics, and ∥Center for Analysis and Synthesis, Lund University , S-221 00 Lund, Sweden
| | - Kimberly A Dick
- Department of Chemical Physics, ‡NanoLund, §Department of Solid State Physics, and ∥Center for Analysis and Synthesis, Lund University , S-221 00 Lund, Sweden
| | - Arkady Yartsev
- Department of Chemical Physics, ‡NanoLund, §Department of Solid State Physics, and ∥Center for Analysis and Synthesis, Lund University , S-221 00 Lund, Sweden
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71
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Shen X, Li Y, Jiang C, Huang J. Temperature Trapping: Energy-Free Maintenance of Constant Temperatures as Ambient Temperature Gradients Change. PHYSICAL REVIEW LETTERS 2016; 117:055501. [PMID: 27517778 DOI: 10.1103/physrevlett.117.055501] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Indexed: 06/06/2023]
Abstract
It is crucial to maintain constant temperatures in an energy-efficient way. Here we establish a temperature-trapping theory for asymmetric phase-transition materials with thermally responsive thermal conductivities. Then we theoretically introduce and experimentally demonstrate a concept of an energy-free thermostat within ambient temperature gradients. The thermostat is capable of self-maintaining a desired constant temperature without the need of consuming energy even though the environmental temperature gradient varies in a large range. As a model application of the concept, we design and show a different type of thermal cloak that has a constant temperature inside its central region in spite of the changing ambient temperature gradient, which is in sharp contrast to all the existing thermal cloaks. This work has relevance to energy-saving heat preservation, and it provides guidance both for manipulating heat flow without energy consumption and for designing new metamaterials with temperature-responsive or field-responsive parameters in many disciplines such as thermotics, optics, electromagnetics, acoustics, mechanics, electrics, and magnetism.
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Affiliation(s)
- Xiangying Shen
- Department of Physics, State Key Laboratory of Surface Physics, and Key Laboratory of Micro and Nano Photonic Structures (MOE), Fudan University, Shanghai 200433, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China
| | - Ying Li
- Department of Mechanics and Engineering Science, Fudan University, Shanghai 200433, China
| | - Chaoran Jiang
- Department of Physics, State Key Laboratory of Surface Physics, and Key Laboratory of Micro and Nano Photonic Structures (MOE), Fudan University, Shanghai 200433, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China
| | - Jiping Huang
- Department of Physics, State Key Laboratory of Surface Physics, and Key Laboratory of Micro and Nano Photonic Structures (MOE), Fudan University, Shanghai 200433, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China
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72
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Low-Temperature Coherent Thermal Conduction in Thin Phononic Crystal Membranes. CRYSTALS 2016. [DOI: 10.3390/cryst6060072] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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73
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Cremons DR, Plemmons DA, Flannigan DJ. Femtosecond electron imaging of defect-modulated phonon dynamics. Nat Commun 2016; 7:11230. [PMID: 27079790 PMCID: PMC4835536 DOI: 10.1038/ncomms11230] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 02/25/2016] [Indexed: 11/09/2022] Open
Abstract
Precise manipulation and control of coherent lattice oscillations via nanostructuring and phonon-wave interference has the potential to significantly impact a broad array of technologies and research areas. Resolving the dynamics of individual phonons in defect-laden materials presents an enormous challenge, however, owing to the interdependent nanoscale and ultrafast spatiotemporal scales. Here we report direct, real-space imaging of the emergence and evolution of acoustic phonons at individual defects in crystalline WSe2 and Ge. Via bright-field imaging with an ultrafast electron microscope, we are able to image the sub-picosecond nucleation and the launch of wavefronts at step edges and resolve dispersion behaviours during propagation and scattering. We discover that the appearance of speed-of-sound (for example, 6 nm ps(-1)) wavefronts are influenced by spatially varying nanoscale strain fields, taking on the appearance of static bend contours during propagation. These observations provide unprecedented insight into the roles played by individual atomic and nanoscale features on acoustic-phonon dynamics.
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Affiliation(s)
- Daniel R Cremons
- Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue SE, Minneapolis, Minnesota 55455, USA
| | - Dayne A Plemmons
- Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue SE, Minneapolis, Minnesota 55455, USA
| | - David J Flannigan
- Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue SE, Minneapolis, Minnesota 55455, USA
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74
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Lim J, Wang HT, Tang J, Andrews SC, So H, Lee J, Lee DH, Russell TP, Yang P. Simultaneous Thermoelectric Property Measurement and Incoherent Phonon Transport in Holey Silicon. ACS NANO 2016; 10:124-32. [PMID: 26650117 DOI: 10.1021/acsnano.5b05385] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Block copolymer patterned holey silicon (HS) was successfully integrated into a microdevice for simultaneous measurements of Seebeck coefficient, electrical conductivity, and thermal conductivity of the same HS microribbon. These fully integrated HS microdevices provided excellent platforms for the systematic investigation of thermoelectric transport properties tailored by the dimensions of the periodic hole array, that is, neck and pitch size, and the doping concentrations. Specifically, thermoelectric transport properties of HS with a neck size in the range of 16-34 nm and a fixed pitch size of 60 nm were characterized, and a clear neck size dependency was shown in the doping range of 3.1 × 10(18) to 6.5 × 10(19) cm(-3). At 300 K, thermal conductivity as low as 1.8 ± 0.2 W/mK was found in HS with a neck size of 16 nm, while optimized zT values were shown in HS with a neck size of 24 nm. The controllable effects of holey array dimensions and doping concentrations on HS thermoelectric performance could aid in improving the understanding of the phonon scattering process in a holey structure and also in facilitating the development of silicon-based thermoelectric devices.
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Affiliation(s)
- Jongwoo Lim
- Materials Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - Hung-Ta Wang
- Department of Chemical and Biological Engineering and Center for Materials for Information Technology, University of Alabama , Tuscaloosa, Alabama 35487, United States
| | - Jinyao Tang
- Department of Chemistry, The University of Hong Kong , Pokfulam, Hong Kong
| | - Sean C Andrews
- Materials Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | | | - Jaeho Lee
- Department of Mechanical and Aerospace Engineering, University of California , Irvine, California 92697, United States
| | - Dong Hyun Lee
- Department of Polymer Science and Engineering, Dankook University , 152, Jukjeon-ro, Suji-gu, Yongin-si, Gyeonggi-do 16890, Korea
- Department of Polymer Science and Engineering, University of Massachusetts , Amherst, Massachusetts 01003, United States
| | - Thomas P Russell
- Department of Polymer Science and Engineering, University of Massachusetts , Amherst, Massachusetts 01003, United States
| | - Peidong Yang
- Materials Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
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