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Ultra-thin titanium nitride films for refractory spectral selectivity

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 نشر من قبل Alexander Roberts PhD
 تاريخ النشر 2018
  مجال البحث فيزياء
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We demonstrate a selectively emitting optical Fabry-Perot resonator based on a few-nm-thin continuous metallic titanium nitride film, separated by a dielectric spacer from an optically thick titanium nitride back-reflector, which exhibits excellent stability at 1070 K against chemical degradation, thin-film instabilities and melting point depression. The structure paves the way to the design and fabrication of refractory thermal emitters using the well-established processes known from the field of multilayer and rugate optical filters. We demonstrate that a few-nanometer thick films of titanium nitride can be stable under operation at temperatures exceeding 1070 K. This type of selective emitter provides a means towards near-infrared thermal emission that could potentially be tailored to the accuracy level known from rugate optical filters.

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