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DOE OSTI · 22308701

Microsecond switchable thermal antenna

Ben-Abdallah, Philippe·Benisty, Henri·Besbes, Mondher
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Abstract

We propose a thermal antenna that can be actively switched on and off at the microsecond scale by means of a phase transition of a metal-insulator material, the vanadium dioxide (VO{sub 2}). This thermal source is made of a periodically patterned tunable VO{sub 2} nanolayer, which support a surface phonon-polariton in the infrared range in their crystalline phase. Using electrodes properly registered with respect to the pattern, the VO{sub 2} phase transition can be locally triggered by ohmic heating so that the surface phonon-polariton can be diffracted by the induced grating, producing a highly directional thermal emission. Conversely, when heating less, the VO{sub 2} layers cool down below the transition temperature, the surface phonon-polariton cannot be diffracted anymore so that thermal emission is inhibited. This switchable antenna could find broad applications in the domain of active thermal coatings or in those of infrared spectroscopy and sensing.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYABSORPTION SPECTROSCOPYANTENNASCOATINGSELECTRODESEMISSIONGRATINGSHEATINGINFRARED SPECTRALAYERSMETALSPERIODICITYPHASE TRANSFORMATIONSPHONONSSUPPORTSSURFACESSWITCHESTRANSITION TEMPERATUREVANADIUM OXIDES

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BibTeXRIS

Ben-Abdallah, Philippe, Benisty, Henri, Besbes, Mondher. 2014-07-21. Microsecond switchable thermal antenna. https://doi.org/10.1063/1.4890517

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