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arXiv:2607.19319

Dark matter searches with a 13 meV threshold superconducting sensor array

Christopher Albert, Lanqing Yuan, Jacob Harris, Ritoban Basu Thakur, Andrew Bear, Karl K. Berggren, Christopher Cappiello, Christopher Curwen, Peter Day, Byeong H. Eom, Arjun Ghosh, William Ho, Nikita Klimovich, Henry G. LeDuc, Karthik Ramanathan, Alejandro Simon

hep-exastro-ph.IMquant-phSubmitted Jul 21, 2026• Announced Jul 22, 2026• Revised Jul 23, 2026 (v2)
v1 · Jul 21, 2026v2 · Jul 23, 2026
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Abstract

Many well-motivated dark matter models predict meV-scale energy deposits in interactions with terrestrial experiments, but this regime is challenging to probe due to a lack of mature single-quantum detectors. Here we report results from QUALIPHIDE (QUAntum LImited PHotons In the Dark Experiment), a cryogenic dark matter search using a $41$-pixel array of energy-resolving microwave kinetic inductance detectors with a $13$ meV threshold, simultaneously used to look for both conversion photons from THz wavelength hidden photon dark matter and phonons from particle-like light dark matter interactions. The experimental design, with on- and off-focus pixels for the hidden photon search, allows for a data-driven background model, giving the experiment discovery potential. A blind analysis of $22$ hours of data shows no significant excess, setting the strongest constraints on the hidden photon kinetic mixing parameter $χ$ over the mass range of $13$-$90$ meV/$c^2$, reaching $1.5\times10^{-12}$ at $50$ meV/$c^2$. These data also yield among the first terrestrial limits on dark matter scattering off nuclei and electrons, down to $5$ MeV/$c^2$ and $20$ keV/$c^2$, respectively. The low threshold also enables future study of the low-energy excess limiting cryogenic detectors and, as we project, will allow for a terahertz-scale QCD axion search with a magnetic field.

Comments
The authors identified a numerical problem in efficiency estimation, which may potentially impact the conclusion of this paper. The manuscript is being revised

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