Reflectance measurements of mm-wave absorbers using frequency-domain continuous wave THz spectroscopy
Image credit: Figure 2Abstract
Due to high dynamic range and ease of use, continuous wave terahertz spectroscopy is an increasingly popular method for optical characterization of components used in cosmic microwave background (CMB) experiments. In this work, we describe an optical testbed that enables simultaneous measurements of transmission and reflection properties of various radiation absorbing dielectric materials, essential components in the reduction of undesired optical loading. To demonstrate the performance of the testbed, we have measured the reflection response of five absorbers commonly used for such applications TKRAM, carbon- and iron-loaded Stycast, HR10, AN72, and an in-house 3D printed absorber across a frequency range of 100 to 500 GHz, for both S- and P-polarization, with incident angles varying from 15 to 45 degrees. We present results on both the specular and scattered reflection response of these absorbers.
Gaganpreet Singh
Postdoc
Gagandeep Kaur
Postdoc
I have worked on spatial mode engineering in periodic photonic bandgap materials such as photonic crystals during my PhD. I am interested in numerical and experimental study of periodic structures, waveguide/cavity based devices designed in such structures for myriad applcations. I am currently working on a prototype of Plasma Haloscope based on wired metamaterials for Axion detection.
Rustam Balafendiev
PhD Student
Rustam Balafendiev received the M.Sc. degree in radiophysics from the School of Physics and Engineering, ITMO University, Saint Petersburg, Russia, in 2021. His current research interests include novel applications of wire metamaterials and holography experiments.
Thomas Gascard
Postdoc
In the hope to contribute to the current efforts of the Cosmology comunity to unveil the early stages of the Universe and its evolution, I did a PhD. in instrumentation for cosmology applications at Cardiff University, which covers design methods, fabrication and experimental characterisation of a Metamaterial-based Lenslet (MetaL) prototype coupled to an antenna fed detector plane. I then joined the CMBeam group to carry on experimental characterisation and qualification of optics for futur cosmology experiments.
Zeshen Bao
BSc Student
My research interests include distributed robotics, mobile computing and programmable matter.
Jón E. Guðmundsson
Assistant Professor
Assistant professor at the University of Iceland and senior research scientist at Stockholm University.