Reference black-body radiation source for emissivity measurements on the frequency range 3–30 THz
Abstract
The emergence of radiation sources in different frequency ranges fuels the demand for techniques for spectrally resolved calibrations of their intensity. Thermal radiation of a perfectly absorbing object (black-body radiation) is used as an etalon in the near-infrared–visible ranges. However, to date, no suitable material exists as a reference for thermal radiation in the frequency range 3–30 THz. In this work, we demonstrate a thermal source that can serve a broad THz frequency range. We employ a moth-eye-structured silicon coated with conductive graphitic film exhibiting absorbance above 99.5%. By using the thermal emission of a silicon-based Salisbury screen heated at a temperature of 60 °C we demonstrate that the moth-eye structure can be used for calibrating THz devices. We also show that the developed approach may allow one to engineer the spectrum of the frequency comb source using a two-layer heterostructure.
Article Details
Journal Info
Applied Physics Letters
American Institute of Physics
Authors (14)
Isaac Appiah Otoo
Center for Photonics Sciences, University of Eastern Finland 1 , P.O. Box 111, FI-80101, Joensuu 80100,
Yuki Hakamada
Department of Physics, The University of Tokyo 2 , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033,
Aleksandr Saushin
Center for Photonics Sciences, University of Eastern Finland 1 , P.O. Box 111, FI-80101, Joensuu 80100,
Maria Cojocari
Center for Photonics Sciences, University of Eastern Finland 1 , P.O. Box 111, FI-80101, Joensuu 80100,
Mikhail Gorbun
Center for Photonics Sciences, University of Eastern Finland 1 , P.O. Box 111, FI-80101, Joensuu 80100,
Janna Penanen
Center for Photonics Sciences, University of Eastern Finland 1 , P.O. Box 111, FI-80101, Joensuu 80100,
Petri Karvinen
Center for Photonics Sciences, University of Eastern Finland 1 , P.O. Box 111, FI-80101, Joensuu 80100,
Shotaro Kawano
Institute for Photon Science and Technology, The University of Tokyo 3 , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033,
Haruyuki Sakurai
Institute for Photon Science and Technology, The University of Tokyo 3 , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033,
Kuniaki Konishi
Institute for Photon Science and Technology, The University of Tokyo 3 , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033,
Irmantas Kašalynas
Department of Optoelectronics, Center for Physical Sciences and Technology (FTMC) 4 , Sauletekio av. 3, Vilnius 10257,
Yuri Svirko
Center for Photonics Sciences, University of Eastern Finland 1 , P.O. Box 111, FI-80101, Joensuu 80100,
Polina Kuzhir
Center for Photonics Sciences, University of Eastern Finland 1 , P.O. Box 111, FI-80101, Joensuu 80100,
Georgy Fedorov
Center for Photonics Sciences, University of Eastern Finland 1 , P.O. Box 111, FI-80101, Joensuu 80100,