title: Planar hyperblack absolute radiometer.
abstract: The absolute responsivity of a planar cryogenic radiometer fabricated from micromachined silicon and having carbon nanotubes, as the absorber and thermistor were measured in the visible and far infrared (free-field terahertz) wavelength range by means of detector-based radiometry. The temperature coefficient of the thermistor near 4.8 K 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.
authors.forename: John
authors.initials: J
authors.lastname: Lehman
authors.forename: Andreas
authors.initials: A
authors.lastname: Steiger
authors.forename: Nathan
authors.initials: N
authors.lastname: Tomlin
authors.forename: Malcolm
authors.initials: M
authors.lastname: White
authors.forename: Mathias
authors.initials: M
authors.lastname: Kehrt
authors.forename: Ivan
authors.initials: I
authors.lastname: Ryger
authors.forename: Michelle
authors.initials: M
authors.lastname: Stephens
authors.forename: Christian
authors.initials: C
authors.lastname: Monte
authors.forename: Ingmar
authors.initials: I
authors.lastname: Mueller
authors.forename: Joerg
authors.initials: J
authors.lastname: Hollandt
authors.forename: Marla
authors.initials: M
authors.lastname: Dowell