We propose the use of superconducting nanowires as both target and sensor for direct detection of sub-GeV dark matter. With excellent sensitivity to small energy deposits on electrons and demonstrated low dark counts, such devices could be used to probe electron recoils from dark matter scattering and absorption processes. We demonstrate the feasibility of this idea using measurements of an existing fabricated tungsten-silicide nanowire prototype with 0.8-eV energy threshold and 4.3 ng with 10 000 s of exposure, which showed no dark counts. The results from this device already place meaningful bounds on dark matter-electron interactions, including the strongest terrestrial bounds on sub-eV dark photon absorption to date. Future expected fabrication on larger scales and with lower thresholds should enable probing of new territory in the direct detection landscape, establishing the complementarity of this approach to other existing proposals.
Bibliographical noteFunding Information:
We thank Tom Dvir, Nadav Katz, and Hadar Steinberg for useful discussions that led to this work, and Eric David Kramer and Eric Kuflik for many helpful discussions. We thank Phil Mauskopf for providing the cryogenic amplifiers used in this experiment. K. K. B. thanks Asimina Arvanitaki and Ken van Tilburg for helpful discussions. The work of Y. H. is supported by the Israel Science Foundation (Grant No. 1112/17), by the Binational Science Foundation (Grant No. 2016155), by the I-CORE Program of the Planning Budgeting Committee (Grant No. 1937/12), by the German Israel Foundation (Grant No. I-2487-303.7/2017), and by the Azrieli Foundation. The work of K. K. B. was supported in part by the DOE under the QuantiSED program, Award No. DE-SC0019129.
© 2019 authors. Published by the American Physical Society.