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John H. Lehman, Michelle S. Stephens, Malcolm G. White, Andreas Steiger, Christian Monte, Joerg Hollandt, Ivan Ryger, Mathias Kehrt, Marla L. Dowell
Abstract
The absolute responsivity of a planar radiometer fabricated from micromachined silicon and having carbon nanotubes as the absorber and thermistor was measured in the visible and far infrared (free-field terahertz) wavelength range by means of detector-based radiometry. The temperature coefficient of the thermistor and noise equivalent power were evaluated along with independent characterization of the window transmittance and specular reflectance of the nanotube absorber. Measurements of absolute power by means of electrical substitution are compared to the German national standard and the uncertainty of the radiometer responsivity as a function of wavelength is summarized.
Lehman, J.
, Stephens, M.
, White, M.
, Steiger, A.
, Monte, C.
, Hollandt, J.
, Ryger, I.
, Kehrt, M.
and Dowell, M.
(2016),
A Planar Hyperblack Absolute Radiometer, Optics Express, [online], https://doi.org/10.1364/OE.24.025911
(Accessed October 14, 2025)