1
|
de Aquino Carvalho JC, Maurin I, Chaves de Souza Segundo P, Laliotis A, de Sousa Meneses D, Bloch D. Spectrally Sharp Near-Field Thermal Emission: Revealing Some Disagreements between a Casimir-Polder Sensor and Predictions from Far-Field Emittance. PHYSICAL REVIEW LETTERS 2023; 131:143801. [PMID: 37862645 DOI: 10.1103/physrevlett.131.143801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 08/01/2023] [Indexed: 10/22/2023]
Abstract
Near-field thermal emission largely exceeds blackbody radiation, owing to spectrally sharp emission in surface polaritons. We turn the Casimir-Polder interaction between Cs(7P_{1/2}) and a sapphire interface into a sensor sharply filtering, at 24.687 THz, the near-field sapphire emission at ∼24.5 THz. The temperature evolution of the sapphire mode is demonstrated. The Cs sensor, sensitive to both dispersion and dissipation, suggests the polariton to be redshifted and sharper, as compared, up to 1100 K, to predictions from far-field sapphire emission, affected by birefringence and multiple resonances.
Collapse
Affiliation(s)
- J C de Aquino Carvalho
- Laboratoire de Physique des Lasers, UMR 7538 du CNRS, Université Sorbonne Paris Nord, 99 av. JB Clément, 93430 Villetaneuse, France
| | - I Maurin
- Laboratoire de Physique des Lasers, UMR 7538 du CNRS, Université Sorbonne Paris Nord, 99 av. JB Clément, 93430 Villetaneuse, France
| | - P Chaves de Souza Segundo
- Laboratoire de Physique des Lasers, UMR 7538 du CNRS, Université Sorbonne Paris Nord, 99 av. JB Clément, 93430 Villetaneuse, France
| | - A Laliotis
- Laboratoire de Physique des Lasers, UMR 7538 du CNRS, Université Sorbonne Paris Nord, 99 av. JB Clément, 93430 Villetaneuse, France
| | | | - D Bloch
- Laboratoire de Physique des Lasers, UMR 7538 du CNRS, Université Sorbonne Paris Nord, 99 av. JB Clément, 93430 Villetaneuse, France
| |
Collapse
|
2
|
Rincón-García L, Thompson D, Mittapally R, Agraït N, Meyhofer E, Reddy P. Enhancement and Saturation of Near-Field Radiative Heat Transfer in Nanogaps between Metallic Surfaces. PHYSICAL REVIEW LETTERS 2022; 129:145901. [PMID: 36240403 DOI: 10.1103/physrevlett.129.145901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 05/27/2022] [Accepted: 09/08/2022] [Indexed: 06/16/2023]
Abstract
Near-field radiative heat transfer (NFRHT) between planar metallic surfaces was computationally explored over five decades ago by Polder and van Hove [Phys. Rev. B 4, 3303 (1971)PLRBAQ0556-280510.1103/PhysRevB.4.3303]. These studies predicted that, as the gap size (d) between the surfaces decreased, the radiative heat flux first increases by several orders of magnitude until d is ∼100 nm after which the heat flux saturates. However, despite both the fundamental and practical importance of these predictions, the combined enhancement and saturation of NFRHT at small gaps in metallic surfaces remains experimentally unverified. Here, we probe NFRHT between planar metallic (Pt, Au) surfaces and show that RHT rates can exceed the far-field rate by over a thousand times when d is reduced to ∼25 nm. More importantly, we show that for small values of d RHT saturates due to the dominant contributions from transverse electric evanescent modes. Our results are in excellent agreement with the predictions of fluctuational electrodynamics and are expected to inform the development of technologies such as near-field thermophotovoltaics, radiative heat-assisted magnetic recording, and nanolithography.
Collapse
Affiliation(s)
- Laura Rincón-García
- Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Dakotah Thompson
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Rohith Mittapally
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Nicolás Agraït
- Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanociencia), C/Faraday 9, E-28049 Madrid, Spain
- Condensed Matter Physics Center (IFIMAC) and Instituto Universitario de Ciencia de Materiales "Nicolás Cabrera" (INC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Edgar Meyhofer
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Pramod Reddy
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| |
Collapse
|
3
|
Song J, Cheng Q, Zhang B, Lu L, Zhou X, Luo Z, Hu R. Many-body near-field radiative heat transfer: methods, functionalities and applications. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2021; 84:036501. [PMID: 33567420 DOI: 10.1088/1361-6633/abe52b] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 02/10/2021] [Indexed: 06/12/2023]
Abstract
Near-field radiative heat transfer (NFRHT) governed by evanescent waves, provides a platform to thoroughly understand the transport behavior of nonradiative photons, and also has great potential in high-efficiency energy harvesting and thermal management at the nanoscale. It is more usual in nature that objects participate in heat transfer process in many-body form rather than the frequently-considered two-body scenarios, and the inborn mutual interactions among objects are important to be understood and utilized for practical applications. The last decade has witnessed considerable achievements on many-body NFRHT, ranging from the establishment of different calculation methods to various unprecedented heat transport phenomena that are distinct from two-body systems. In this invited review, we introduce concisely the basic physics of NFRHT, lay out various theoretical methods to deal with many-body NFRHT, and highlight unique functionalities realized in many-body systems and the resulting applications. At last, the key challenges and opportunities of many-body NFRHT in terms of fundamental physics, experimental validations, and potential applications are outlined and discussed.
Collapse
Affiliation(s)
- Jinlin Song
- School of Electrical and Information Engineering, Wuhan Institute of Technology, Wuhan 430025, Hubei, People's Republic of China
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei, People's Republic of China
| | - Qiang Cheng
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei, People's Republic of China
| | - Bo Zhang
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei, People's Republic of China
| | - Lu Lu
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei, People's Republic of China
| | - Xinping Zhou
- School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei, People's Republic of China
| | - Zixue Luo
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei, People's Republic of China
| | - Run Hu
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei, People's Republic of China
| |
Collapse
|
4
|
Lucchesi C, Vaillon R, Chapuis PO. Radiative heat transfer at the nanoscale: experimental trends and challenges. NANOSCALE HORIZONS 2021; 6:201-208. [PMID: 33533775 DOI: 10.1039/d0nh00609b] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Energy transport theories are being revisited at the nanoscale, as macroscopic laws known for a century are broken at dimensions smaller than those associated with energy carriers. For thermal radiation, where the typical dimension is provided by Wien's wavelength, Planck's law and associated concepts describing surface-to-surface radiative transfer have to be replaced by a full electromagnetic framework capturing near-field radiative heat transfer (photon tunnelling between close bodies), interference effects and sub-wavelength thermal emission (emitting body of small size). It is only during the last decade that nanotechnology has allowed for many experimental verifications - with a recent boom - of the large increase of radiative heat transfer at the nanoscale. In this minireview, we highlight the parameter space that has been investigated until now, showing that it is limited in terms of inter-body distance, temperature and object size, and provide clues about possible thermal-energy harvesting, sensing and management applications. We also provide an outlook on open topics, underlining some difficulties in applying single-wavelength approaches to broadband thermal emitters while acknowledging the promise of thermal nanophotonics and observing that molecular/chemical viewpoints have been hardly addressed.
Collapse
Affiliation(s)
- Christophe Lucchesi
- Univ Lyon, CNRS, INSA-Lyon, Université Claude Bernard Lyon 1, CETHIL UMR5008, F-69621 Villeurbanne, France.
| | | | | |
Collapse
|
5
|
Zou Y, Pan H, Huang S, Chen P, Yan H, An Z. Non-Planckian infrared emission from GaAs devices with electrons and lattice out-of-thermal-equilibrium. OPTICS EXPRESS 2021; 29:1244-1250. [PMID: 33726343 DOI: 10.1364/oe.415232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 12/20/2020] [Indexed: 06/12/2023]
Abstract
With the downscaled device size, electrons in semiconductor electronics are often electrically driven out-of-thermal-equilibrium with hosting lattices for their functionalities. The thereby electrothermal Joule heating to the lattices can be visualized directly by the noncontact infrared radiation thermometry with the hypothetic Planck distribution at a single characteristic temperature. We report here that the infrared emission spectrum from electrically biased GaAs devices deviates obviously from Planck distribution, due to the additional contribution from non-equilibrium hot electrons whose effective temperature reaches much higher than that of the lattice (Te>Tl). The evanescent infrared emission from these hot electrons is out-coupled by a near-field metamaterial grating and is hence made significant to the total far-field emission spectrum. Resonant emission peak has also been observed when the electron hotspots are managed to overlap spatially with the optical hotspots at the grating resonance. Our work opens a new direction to study nonequilibrium dynamics with (non-Planckian) infrared emission spectroscopy and provides important implications into the microscopic energy dissipation and heat management in nanoelectronics.
Collapse
|
6
|
Buahom P, Wang C, Alshrah M, Wang G, Gong P, Tran MP, Park CB. Wrong expectation of superinsulation behavior from largely-expanded nanocellular foams. NANOSCALE 2020; 12:13064-13085. [PMID: 32542255 DOI: 10.1039/d0nr01927e] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
This work aims to predict the thermal conductivity of microcellular and nanocellular thermal insulation foams to explore the correlation between the cellular structure and the thermal insulating properties. Closed-cell foam consisting of cell walls and struts was used as the base geometry for modeling. The mathematical correlations to calculate the thickness of cell walls and the diameter of struts for a given cell size, the void fraction and the volume fraction of polymer located in struts were investigated. Then, a mathematical model for the conductive thermal conductivity including the dependency on the void fraction, the strut fraction and the Knudsen effect for gas was introduced. The radiative thermal conductivity was determined by analyzing the attenuation of radiative energy by absorption and scattering based on Mie's theory together with electromagnetic wave interference, as well as interference of propagating waves and tunneling of the radiative energy by evanescent waves in the cells. The thermal conductivity model was validated by experimental data and used to predict the thermal conductivity of polystyrene (PS) and poly(methyl methacrylate) (PMMA) foams at various cell sizes and volume expansion ratios. It was found that the radiative thermal conductivity plays a crucial role in nanocellular foam. The trade-off between the cell size and cell wall thickness when cell walls become thinner and highly transparent to thermal radiation was demonstrated, leading to the optimal volume expansion ratio at which the thermal conductivities were minimized. Perspectives for the manufacture of high-performance thermal insulation foams are also discussed.
Collapse
Affiliation(s)
- Piyapong Buahom
- Microcellular Plastics Manufacturing Laboratory (MPML), Department of Mechanical & Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, M5S 3G8, Ontario, Canada.
| | - Chongda Wang
- Microcellular Plastics Manufacturing Laboratory (MPML), Department of Mechanical & Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, M5S 3G8, Ontario, Canada.
| | - Mohammed Alshrah
- Microcellular Plastics Manufacturing Laboratory (MPML), Department of Mechanical & Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, M5S 3G8, Ontario, Canada.
| | - Guilong Wang
- Microcellular Plastics Manufacturing Laboratory (MPML), Department of Mechanical & Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, M5S 3G8, Ontario, Canada. and Cellular Polymer Science & Technology Laboratory, School of Materials Science & Engineering, Shandong University, 250061, Shandong, China
| | - Pengjian Gong
- Microcellular Plastics Manufacturing Laboratory (MPML), Department of Mechanical & Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, M5S 3G8, Ontario, Canada. and College of Polymer Science and Engineering, Sichuan University, 610065, Chengdu, China
| | - Minh-Phuong Tran
- Microcellular Plastics Manufacturing Laboratory (MPML), Department of Mechanical & Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, M5S 3G8, Ontario, Canada. and University Grenoble Alpes, CEA, LETI, 17 Avenue des Martyrs, 38000, Grenoble, France
| | - Chul B Park
- Microcellular Plastics Manufacturing Laboratory (MPML), Department of Mechanical & Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, M5S 3G8, Ontario, Canada.
| |
Collapse
|
7
|
Fiorino A, Thompson D, Zhu L, Song B, Reddy P, Meyhofer E. Giant Enhancement in Radiative Heat Transfer in Sub-30 nm Gaps of Plane Parallel Surfaces. NANO LETTERS 2018; 18:3711-3715. [PMID: 29701988 DOI: 10.1021/acs.nanolett.8b00846] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Radiative heat transfer rates that exceed the blackbody limit by several orders of magnitude are expected when the gap size between plane parallel surfaces is reduced to the nanoscale. To date, experiments have only realized enhancements of ∼100 fold as the smallest gap sizes in radiative heat transfer studies have been limited to ∼50 nm by device curvature and particle contamination. Here, we report a 1,200-fold enhancement with respect to the far-field value in the radiative heat flux between parallel planar silica surfaces separated by gaps as small as ∼25 nm. Achieving such small gap sizes and the resultant dramatic enhancement in near-field energy flux is critical to achieve a number of novel near-field based nanoscale energy conversion systems that have been theoretically predicted but remain experimentally unverified.
Collapse
|
8
|
Lang S, Sharma G, Molesky S, Kränzien PU, Jalas T, Jacob Z, Petrov AY, Eich M. Dynamic measurement of near-field radiative heat transfer. Sci Rep 2017; 7:13916. [PMID: 29066840 PMCID: PMC5655434 DOI: 10.1038/s41598-017-14242-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 10/06/2017] [Indexed: 11/24/2022] Open
Abstract
Super-Planckian near-field radiative heat transfer allows effective heat transfer between a hot and a cold body to increase beyond the limits long known for black bodies. Until present, experimental techniques to measure the radiative heat flow relied on steady-state systems. Here, we present a dynamic measurement approach based on the transient plane source technique, which extracts thermal properties from a temperature transient caused by a step input power function. Using this versatile method, that requires only single sided contact, we measure enhanced radiative conduction up to 16 times higher than the blackbody limit on centimeter sized glass samples without any specialized sample preparation or nanofabrication.
Collapse
Affiliation(s)
- S Lang
- Institute of Optical and Electronic Materials, Hamburg University of Technology, Eissendorfer Strasse 38, 21073, Hamburg, Germany.
| | - G Sharma
- Institute of Optical and Electronic Materials, Hamburg University of Technology, Eissendorfer Strasse 38, 21073, Hamburg, Germany
| | - S Molesky
- University of Alberta, Department of Electrical and Computer Engineering, 9107 - 116 Street, Edmonton, T6G 2V4, Canada
| | - P U Kränzien
- Institute of Optical and Electronic Materials, Hamburg University of Technology, Eissendorfer Strasse 38, 21073, Hamburg, Germany
| | - T Jalas
- Institute of Optical and Electronic Materials, Hamburg University of Technology, Eissendorfer Strasse 38, 21073, Hamburg, Germany
| | - Z Jacob
- University of Alberta, Department of Electrical and Computer Engineering, 9107 - 116 Street, Edmonton, T6G 2V4, Canada.,Birck Nanotechnology Center, School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN, 47906, USA
| | - A Yu Petrov
- Institute of Optical and Electronic Materials, Hamburg University of Technology, Eissendorfer Strasse 38, 21073, Hamburg, Germany.,ITMO University, 49 Kronverkskii Ave., St. Petersburg, 197101, Russia
| | - M Eich
- Institute of Optical and Electronic Materials, Hamburg University of Technology, Eissendorfer Strasse 38, 21073, Hamburg, Germany.,Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Strasse 1, 21502, Geesthacht, Germany
| |
Collapse
|
9
|
Fernández-Hurtado V, García-Vidal FJ, Fan S, Cuevas JC. Enhancing Near-Field Radiative Heat Transfer with Si-based Metasurfaces. PHYSICAL REVIEW LETTERS 2017; 118:203901. [PMID: 28581797 DOI: 10.1103/physrevlett.118.203901] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Indexed: 06/07/2023]
Abstract
We demonstrate in this work that the use of metasurfaces provides a viable strategy to largely tune and enhance near-field radiative heat transfer between extended structures. In particular, using a rigorous coupled wave analysis, we predict that Si-based metasurfaces featuring two-dimensional periodic arrays of holes can exhibit a room-temperature near-field radiative heat conductance much larger than any unstructured material to date. We show that this enhancement, which takes place in a broad range of separations, relies on the possibility to largely tune the properties of the surface plasmon polaritons that dominate the radiative heat transfer in the near-field regime.
Collapse
Affiliation(s)
- V Fernández-Hurtado
- Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain
- Department of Electrical Engineering, and Ginzton Laboratory, Stanford University, Stanford, California 94305, USA
- Department of Physics, University of Konstanz, D-78457 Konstanz, Germany
| | - F J García-Vidal
- Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain
- Donostia International Physics Center (DIPC), Donostia/San Sebastián 20018, Spain
| | - Shanhui Fan
- Department of Electrical Engineering, and Ginzton Laboratory, Stanford University, Stanford, California 94305, USA
| | - J C Cuevas
- Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain
- Department of Physics, University of Konstanz, D-78457 Konstanz, Germany
| |
Collapse
|
10
|
Study of radiative heat transfer in Ångström- and nanometre-sized gaps. Nat Commun 2017; 8:ncomms14479. [PMID: 28198467 PMCID: PMC5330859 DOI: 10.1038/ncomms14479] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 01/03/2017] [Indexed: 11/30/2022] Open
Abstract
Radiative heat transfer in Ångström- and nanometre-sized gaps is of great interest because of both its technological importance and open questions regarding the physics of energy transfer in this regime. Here we report studies of radiative heat transfer in few Å to 5 nm gap sizes, performed under ultrahigh vacuum conditions between a Au-coated probe featuring embedded nanoscale thermocouples and a heated planar Au substrate that were both subjected to various surface-cleaning procedures. By drawing on the apparent tunnelling barrier height as a signature of cleanliness, we found that upon systematically cleaning via a plasma or locally pushing the tip into the substrate by a few nanometres, the observed radiative conductances decreased from unexpectedly large values to extremely small ones—below the detection limit of our probe—as expected from our computational results. Our results show that it is possible to avoid the confounding effects of surface contamination and systematically study thermal radiation in Ångström- and nanometre-sized gaps. Here, Cui et al. report radiative heat transfer in few Ångström to 5 nm gap sizes, between a gold-coated probe and a heated planar gold substrate subjected to various surface cleaning procedures. They found that insufficiently cleaned probes and substrates led to unexpectedly large radiative thermal conductances.
Collapse
|
11
|
Giant heat transfer in the crossover regime between conduction and radiation. Nat Commun 2017; 8:ncomms14475. [PMID: 28198369 PMCID: PMC5330847 DOI: 10.1038/ncomms14475] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 01/03/2017] [Indexed: 11/08/2022] Open
Abstract
Heat is transferred by radiation between two well-separated bodies at temperatures of finite difference in vacuum. At large distances the heat transfer can be described by black body radiation, at shorter distances evanescent modes start to contribute, and at separations comparable to inter-atomic spacing the transition to heat conduction should take place. We report on quantitative measurements of the near-field mediated heat flux between a gold coated near-field scanning thermal microscope tip and a planar gold sample at nanometre distances of 0.2-7 nm. We find an extraordinary large heat flux which is more than five orders of magnitude larger than black body radiation and four orders of magnitude larger than the values predicted by conventional theory of fluctuational electrodynamics. Different theories of phonon tunnelling are not able to describe the observations in a satisfactory way. The findings demand modified or even new models of heat transfer across vacuum gaps at nanometre distances.
Collapse
|
12
|
Radiative heat transfer exceeding the blackbody limit between macroscale planar surfaces separated by a nanosize vacuum gap. Nat Commun 2016; 7:12900. [PMID: 27682992 PMCID: PMC5056409 DOI: 10.1038/ncomms12900] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 08/12/2016] [Indexed: 12/24/2022] Open
Abstract
Using Rytov's fluctuational electrodynamics framework, Polder and Van Hove predicted that radiative heat transfer between planar surfaces separated by a vacuum gap smaller than the thermal wavelength exceeds the blackbody limit due to tunnelling of evanescent modes. This finding has led to the conceptualization of systems capitalizing on evanescent modes such as thermophotovoltaic converters and thermal rectifiers. Their development is, however, limited by the lack of devices enabling radiative transfer between macroscale planar surfaces separated by a nanosize vacuum gap. Here we measure radiative heat transfer for large temperature differences (∼120 K) using a custom-fabricated device in which the gap separating two 5 × 5 mm2 intrinsic silicon planar surfaces is modulated from 3,500 to 150 nm. A substantial enhancement over the blackbody limit by a factor of 8.4 is reported for a 150-nm-thick gap. Our device paves the way for the establishment of novel evanescent wave-based systems. Evanescent coupling between surfaces separated by a distance smaller than the thermal wavelength can lead to radiative heat transfer greater than the blackbody limit. Here, the authors demonstrate this between two macroscopic-scale surfaces, paving the way to harnessing the effect in thermal devices.
Collapse
|
13
|
Radiative heat transfer in the extreme near field. Nature 2015; 528:387-91. [DOI: 10.1038/nature16070] [Citation(s) in RCA: 266] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 10/01/2015] [Indexed: 12/22/2022]
|
14
|
Kloppstech K, Könne N, Worbes L, Hellmann D, Kittel A. Dancing the tight rope on the nanoscale--Calibrating a heat flux sensor of a scanning thermal microscope. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2015; 86:114902. [PMID: 26628160 DOI: 10.1063/1.4935586] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report on a precise in situ procedure to calibrate the heat flux sensor of a near-field scanning thermal microscope. This sensitive thermal measurement is based on 1ω modulation technique and utilizes a hot wire method to build an accessible and controllable heat reservoir. This reservoir is coupled thermally by near-field interactions to our probe. Thus, the sensor's conversion relation V(th)(Q(GS)*) can be precisely determined. V(th) is the thermopower generated in the sensor's coaxial thermocouple and Q(GS)* is the thermal flux from reservoir through the sensor. We analyze our method with Gaussian error calculus with an error estimate on all involved quantities. The overall relative uncertainty of the calibration procedure is evaluated to be about 8% for the measured conversion constant, i.e., (2.40 ± 0.19) μV/μW. Furthermore, we determine the sensor's thermal resistance to be about 0.21 K/μW and find the thermal resistance of the near-field mediated coupling at a distance between calibration standard and sensor of about 250 pm to be 53 K/μW.
Collapse
Affiliation(s)
- K Kloppstech
- Department of Physics, University of Oldenburg, Oldenburg 26129, Germany
| | - N Könne
- Department of Physics, University of Oldenburg, Oldenburg 26129, Germany
| | - L Worbes
- Department of Physics, University of Oldenburg, Oldenburg 26129, Germany
| | - D Hellmann
- Department of Physics, University of Oldenburg, Oldenburg 26129, Germany
| | - A Kittel
- Department of Physics, University of Oldenburg, Oldenburg 26129, Germany
| |
Collapse
|
15
|
Impacts of propagating, frustrated and surface modes on radiative, electrical and thermal losses in nanoscale-gap thermophotovoltaic power generators. Sci Rep 2015; 5:11626. [PMID: 26112658 PMCID: PMC4481525 DOI: 10.1038/srep11626] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 06/01/2015] [Indexed: 11/08/2022] Open
Abstract
The impacts of radiative, electrical and thermal losses on the performances of nanoscale-gap thermophotovoltaic (nano-TPV) power generators consisting of a gallium antimonide cell paired with a broadband tungsten and a radiatively-optimized Drude radiator are analyzed. Results reveal that surface mode mediated nano-TPV power generation with the Drude radiator outperforms the tungsten radiator, dominated by frustrated modes, only for a vacuum gap thickness of 10 nm and if both electrical and thermal losses are neglected. The key limiting factors for the Drude- and tungsten-based devices are respectively the recombination of electron-hole pairs at the cell surface and thermalization of radiation with energy larger than the cell absorption bandgap. A design guideline is also proposed where a high energy cutoff above which radiation has a net negative effect on nano-TPV power output due to thermal losses is determined. It is shown that the power output of a tungsten-based device increases by 6.5% while the cell temperature decreases by 30 K when applying a high energy cutoff at 1.45 eV. This work demonstrates that design and optimization of nano-TPV devices must account for radiative, electrical and thermal losses.
Collapse
|
16
|
Song B, Ganjeh Y, Sadat S, Thompson D, Fiorino A, Fernández-Hurtado V, Feist J, Garcia-Vidal FJ, Cuevas JC, Reddy P, Meyhofer E. Enhancement of near-field radiative heat transfer using polar dielectric thin films. NATURE NANOTECHNOLOGY 2015; 10:253-258. [PMID: 25705866 DOI: 10.1038/nnano.2015.6] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 01/10/2015] [Indexed: 06/04/2023]
Abstract
Thermal radiative emission from a hot surface to a cold surface plays an important role in many applications, including energy conversion, thermal management, lithography, data storage and thermal microscopy. Recent studies on bulk materials have confirmed long-standing theoretical predictions indicating that when the gap between the surfaces is reduced to tens of nanometres, well below the peak wavelength of the blackbody emission spectrum, the radiative heat flux increases by orders of magnitude. However, despite recent attempts, whether such enhancements can be obtained in nanoscale dielectric films thinner than the penetration depth of thermal radiation, as suggested by theory, remains experimentally unknown. Here, using an experimental platform that comprises a heat-flow calorimeter with a resolution of about 100 pW (ref. 7), we experimentally demonstrate a dramatic increase in near-field radiative heat transfer, comparable to that obtained between bulk materials, even for very thin dielectric films (50-100 nm) when the spatial separation between the hot and cold surfaces is comparable to the film thickness. We explain these results by analysing the spectral characteristics and mode shapes of surface phonon polaritons, which dominate near-field radiative heat transport in polar dielectric thin films.
Collapse
Affiliation(s)
- Bai Song
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Yashar Ganjeh
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Seid Sadat
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Dakotah Thompson
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Anthony Fiorino
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Víctor Fernández-Hurtado
- Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, Madrid 28049, Spain
| | - Johannes Feist
- Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, Madrid 28049, Spain
| | - Francisco J Garcia-Vidal
- 1] Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, Madrid 28049, Spain [2] Donostia International Physics Center (DIPC), Donostia/San Sebastián 20018, Spain
| | - Juan Carlos Cuevas
- Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, Madrid 28049, Spain
| | - Pramod Reddy
- 1] Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA [2] Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Edgar Meyhofer
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| |
Collapse
|
17
|
Sasihithlu K, Narayanaswamy A. Near-field radiative transfer between two unequal sized spheres with large size disparities. OPTICS EXPRESS 2014; 22:14473-14492. [PMID: 24977544 DOI: 10.1364/oe.22.014473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We compute near-field radiative transfer between two spheres of unequal radii R1 and R2 such that R2 ≲ 40R1. For R2 = 40R1, the smallest gap to which we have been able to compute radiative transfer is d = 0.016R1. To accomplish these computations, we have had to modify existing methods for computing near-field radiative transfer between two spheres in the following ways: (1) exact calculations of coefficients of vector translation theorem are replaced by approximations valid for the limit d ≪ R1, and (2) recursion relations for a normalized form of translation coefficients are derived which enable us to replace computations of spherical Bessel and Hankel functions by computations of ratios of spherical Bessel or spherical Hankel functions. The results are then compared with the predictions of the modified proximity approximation.
Collapse
|