Institut Néel and its scientific surroundings : ESRF, ILL, CEA, Minatec

Transfert thermique en champ proche

Staff : Joel Chevrier
Postdoc : Peter van Zwol
PhD : Alessandro Siria (now at LPMCN in Lyon)



Radiative heat transfer at the nanoscale

Heat can be exchanged between two surfaces through emission and absorption of thermal radiation. It has been predicted theoretically that for distances smaller than the peak wavelength of the blackbody spectrum, radiative heat transfer can be increased by the contribution of evanescent waves. This contribution can be viewed as energy tunnelling through the gap between the surfaces. Although these effects have already been observed, a detailed quantitative comparison between theory and experiments in the nanometre regime is still lacking. Here, we report an experimental setup that allows measurement of conductance for gaps varying between 30 nm and 2.5 µm. Our measurements pave the way for the design of submicrometre nanoscale heaters that could be used for heat-assisted magnetic recording or heat-assisted lithography.



Tuning near field radiative heat flux through surface excitations with a metal insulator transition

The control of heat flow is a formidable challenge due to lack of good thermal insulators. However as a result of progress made for radiative heat transfer in near field it was recently theoretically predicted that, by tuning electronic excitations on surfaces, large radiative heat flow contrasts, and thus better control of heat flow, may be achieved. Here we show experimentally that the phase transition of VO2 entails a change of surface polariton states that significantly affects radiative heat transfer in near field. In addition we observed a strong dependence of the far field limit on the VO2 layer thickness. We found that in all cases the Derjaguin approximation correctly predicted radiative heat transfer in near field, but it underestimated the far field limit. Our results indicate that a large contrast in heat flow can be realized in near field that is otherwise not attainable inside bulk material or in far field.



Publications :

Tuning near field radiative heat flux through surface excitations with a metal insulator transition
P.J. van Zwol, L. Ranno, J. Chevrier
Phys. Rev. Lett. 108, 234301 (2012)

Emissivity measurements with an atomic force microscope
P.J. van Zwol, L. Ranno, and J. Chevrier
J. Appl. Phys. 111, 063110 (2012)

Phonon polaritons enhance near-field thermal transfer across the phase transition of VO2
P.J. van Zwol, K. Joulain, P. Ben-Abdallah, and J. Chevrier
Phys. Rev. B 84, 161413 (2011)

Fast nanoscale heat-flux modulation with phase-change materials
P.J. van Zwol, K. Joulain, P. Ben Abdallah, J. J. Greffet, and J. Chevrier
Phys. Rev. B 83, 201404(R) (2011)

Radiative heat transfer at the nanoscale
E. Rousseau, A. Siria, G. Jourdan, S. Volz, F. Comin, J. Chevrier, and J.-J. Greffet
Nature Photonics 3, 514 (2009)

Fundings :

ANR Blanc 2009 : projet SOURCES-TPV
Matériaux micro et nanostructurés stratifiés optimisés pour la conversion d’énergie thermophotovoltaïque

Links :

Faits marquants 2010 : Heat flux at the nanoscale

Joel Chevrier : Nanotech Research Programs

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