The development of KID based spectroscopy aims to provide different technological options to study millimeter waves at different energy resolutions R=Δν/ν ranging from 10 to 10,000.

Among other astrophysical challenges, two are of greater importance to us.

The first is to separate the so called B modes of the Cosmic Microwave Background polarization from those of the foreground emission of galactic dust and synchrotron.

The second is to map the intensity fluctuations of the Carbon II line in early galaxies to understand better galaxy evolution and star formation at the epoch of reionization.

For low resolution (R 10), we have already coupled KIDs to a Martin-Puplett interferometer on KISS and CONCERTO. We are investigating another solution based KID arrays on wedge-shaped substrates acting as Fabry-Perot cavity. For R 100, we are investigating on-chip spectroscopy with superconducting resonant filters. For even higher resolutions R of 1000 to 10,000, sub-gap modes of KID made out of particular superconducting materials are explored as a technological option.

Updated on 21 février 2022