Near-field Thermal emission of sapphire at high-T: precisely locating the T dependent polariton resonances in view of energy conversion

João Carlos de Aquino Carvalho (1) , Isabelle Maurin (1) , Athanasios Laliotis (1) , Daniel Bloch (1) , Domingos de Sousa Meneses (2)

1 LPL - Laboratoire de Physique des Lasers
2 CEMHTI - Conditions Extrêmes et Matériaux : Haute Température et Irradiation

In the near-field of a hot (T  1100 K) window, we use atom spectroscopy as an ultra narrow spectral filter to probe the T-dependent surface polariton resonance of sapphire (~12.2µm). The results agree only partly with predictions derived from broadband far-field emissivity. Sapphire birefringence makes predictions difficult, but adds to versatility. Near-field thermal emission could be converted into a molecular excitation, opening a path to electrical conversion.

Mots clés: surface polariton; sapphire; thermal excitation; near-field; casimir-Polder; optical characterization; Near-field Surface polariton Casimir-Polder interaction birefringence; Near-field; Surface polariton; Casimir-Polder interaction birefringence

Domaines: Science des matériaux [cond-mat.mtrl-sci]; Optique [physics.optics]; Physique Atomique [physics.atom-ph]

João Carlos de Aquino Carvalho, Isabelle Maurin, Athanasios Laliotis, Daniel Bloch, Domingos de Sousa Meneses. Near-field Thermal emission of sapphire at high-T: precisely locating the T dependent polariton resonances in view of energy conversion. Workshop on Thermal radiation to electrical energy conversion TREE 2022, CNRS-INSI IESèMontpellier et ESIEE, Nov 2022, Noisy-le-Grand, France. ⟨hal-03856658⟩