Wideband Direct Detection Constraints on Hidden Photon Dark Matter with the QUALIPHIDE Experiment

We report direction detection constraints on the presence of hidden photon dark matter with masses between 20–30  μ⁢eV c⁻², using a cryogenic emitter-receiver-amplifier spectroscopy setup designed as the first iteration of QUALIPHIDE (quantum limited photons in the dark experiment). A metallic dish sources conversion photons, from hidden photon kinetic mixing, onto a horn antenna which is coupled to a 𝐶 band kinetic inductance traveling wave parametric amplifier, providing for near quantum-limited noise performance. We demonstrate a first probing of the kinetic mixing parameter 𝜒 to the 10⁻¹² level for the majority of hidden photon masses in this region. These results not only represent stringent constraints on new dark matter parameter space, but are also the first demonstrated use of wideband quantum-limited amplification for astroparticle applications.