Detecting light at the single-photon level is one of the pillars of emergent photonic technologies. This is realized through state-of-the-art superconducting detectors that offer efficient, broadband and fast response. However, the use of superconducting thin films with low TC limits their operation temperature below 4K. In this work, we demonstrate proof-of-concept nanodetectors based on exfoliated, two-dimensional cuprate superconductor Bi2Sr2CaCu2O8-{\delta} (BSCCO) that exhibit single-photon sensitivity at telecom wavelength at a record temperature of T = 20K. These non-optimized devices exhibit a slow (ms) reset time and a low detection efficiency (10^(-4)). We realize the elusive prospect of single-photon sensitivity on a high-TC nanodetector thanks to a novel approach, combining van der Waals fabrication techniques and a non-invasive nanopatterning based on light ion irradiation. This result paves the way for broader application of single-photon technologies, relaxing the cryogenic constraints for single-photon detection at telecom wavelength.
@article{arxiv.2208.05044,
title = {Two-dimensional cuprate nanodetector with single photon sensitivity at T = 20 K},
author = {Rafael Luque Merino and Paul Seifert and Jose Duran Retamal and Roop Mech and Takashi Taniguchi and Kenji Watanabe and Kazuo Kadowaki and Robert H. Hadfield and Dmitri K. Efetov},
journal= {arXiv preprint arXiv:2208.05044},
year = {2022}
}