arXiv subjects

Alexander V. Chiginev

Publications and source records attributed to Alexander V. Chiginev.

2 recordsLinked to original sources

arXiv2025

Search for dark-matter axions beyond the quantum limit: the Cosmological Axion Sarov Haloscope (CASH) proposal

Firmly established in astrophysical observations, dark matter evades direct detection in experiments. Axions and axion-like particles are among the leading dark-matter candidates, and numerous attempts to detect them in laboratories have been performed. Here, we propose to advance these efforts substantially, extending the sensitivity for dark-matter axions in the mass range $(38-54)~μ$eV down to the axion-photon couplings $g_{aγγ}\lesssim \left(10^{-14}-10^{-15}\right)$ GeV$^{-1}$, motivated by generic models of Quantum Chromodynamics axion. Single-photon detectors operating at ultra-low temperatures are key elements of the experiment. The projected sensitivity will be reached in one year of data taking with magnetic field of $(1-10)$ T, making Cosmological Axion Sarov Haloscope (CASH) the most sensitive haloscope in this mass range.

hep-ph↗

arXiv2025

Josephson microwave photon detector operating at 0.7 K

We predict that the threshold detectors based on Al Josephson junctions, with critical currents below 100 nA, exhibiting a phase diffusion regime, can be exploited for the microwave photon detection both at 17 mK and 700 mK. We demonstrate a detection of two- and one-photon energies at 5 GHz with 90% and 15% efficiency and dark count time of about 0.1 s and 0.01 s, respectively. The observed weak temperature dependence of the detector's performance in the sub-kelvin range fully confirms its phase-diffusion mode of operation. On the other hand, these results show that inevitable thermal fluctuations are not the main source of the detector noise. Consequently, there is still a room to optimize the detector's performance. These results are important for axion search experiments in the range of 5-25 GHz (20-100 $μ$eV).

cond-mat.dis-nn↗