We propose the use of transition-edge sensor (TES) single-photon detectors as a simultaneous target and sensor for direct dark matter searches, and report results from the first search of this kind. We perform a 489 h science run with a TES device optimized for the detection of 1064 nm photons, with a mass of ~0.2 ng and an energy threshold of ~0.3 eV, and set new limits on dark matter interactions with both electrons and nucleons for dark matter with mass below the MeV scale. With their excellent energy resolution, TESs enable search strategies that are complementary to recent results from superconducting nanowire single-photon detectors and kinetic inductance detectors. We show that next-generation TES arrays hold promise to probe new regions of light dark matter parameter space.
@article{arxiv.2506.18982,
title = {First direct search for light dark matter interactions in a transition-edge sensor},
author = {Christina Schwemmbauer and Guy Daniel Hadas and Yonit Hochberg and Katharina-Sophie Isleif and Friederike Januschek and Benjamin V. Lehmann and Axel Lindner and Adriana E. Lita and Manuel Meyer and Gulden Othman and Elmeri Rivasto and José Alejandro Rubiera Gimeno},
journal= {arXiv preprint arXiv:2506.18982},
year = {2025}
}