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arXiv · 0905.4710

Temperature dependence of the dielectric permittivity of CaF2, BaF2 and Al2O3: application to the prediction of a temperature dependent van der Waals surface interaction exerted onto a neighbouring Cs (8P{3/2}) atom

Thierry Passerat De Silans·Isabelle Maurin·Pedro Chaves De Souza Segundo·Solomon Saltiel·Marie-Pascale Gorza·Martial Ducloy·Daniel Bloch·Domingo De Sousa Meneses·Patrick Echegut
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Abstract

The temperature behaviour in the range 22\degree C to 500\degree C of the dielectric permittivity in the infrared range is investigated for CaF2, BaF2 and Al2O3 through reflectivity measurements. The dielectric permittivity is retrieved by fitting reflectivity spectra with a model taking into account multiphonon contributions. The results extrapolated from the measurements are applied to predict a temperature-dependent atom-surface van der Waals interaction. We specifically consider as the atom of interest Cs (8P3/2), the most relevant virtual couplings of which, fall in the range of thermal radiation and are located in the vicinity of the reststrahlen band of fluoride materials.

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Thierry Passerat De Silans, Isabelle Maurin, Pedro Chaves De Souza Segundo, Solomon Saltiel, Marie-Pascale Gorza, Martial Ducloy, Daniel Bloch, Domingo De Sousa Meneses, Patrick Echegut. 2009-05-28. Temperature dependence of the dielectric permittivity of CaF2, BaF2 and Al2O3: application to the prediction of a temperature dependent van der Waals surface interaction exerted onto a neighbouring Cs (8P{3/2}) atom. https://doi.org/10.1088/0953-8984%2F21%2F25%2F255902

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