Photodetectors based on nano-structured superconducting thin films are currently some of the most sensitive quantum sensors and are key enabling technologies in such broad areas as quantum information, quantum computation and radio-astronomy. However, their broader use is held back by the low operation temperatures which require expensive cryostats. Here, we demonstrate a nitrogen cooled superconducting transition edge sensor, which shows orders of magnitude improved performance characteristics of any superconducting detector operated above 77K, with a responsivity of 9.61x10^4 V/W, noise equivalent power of 15.9 fW/Hz-1/2 and operation speeds up to GHz frequencies. It is based on van der Waals heterostructures of the high temperature superconductor Bi2Sr2CaCu2O8, which are shaped into nano-wires with ultra-small form factor. To highlight the versatility of the detector we demonstrate its fabrication and operation on a telecom grade SiN waveguide chip. Our detector significantly relaxes the demands of practical applications of superconducting detectors and displays its huge potential for photonics based quantum applications.
@article{arxiv.2006.03130,
title = {A liquid nitrogen cooled superconducting transition edge sensor with ultra-high responsivity and GHz operation speeds},
author = {Paul Seifert and Jose Ramon Duran Retamal and Rafael Luque Merino and Hanan Herzig Sheinfux and John N. Moore and Mohammed Ali Aamir and Takashi Taniguchi and Kenji Wantanabe and Kazuo Kadowaki and Massimo Artiglia and Marco Romagnoli and Dmitri K. Efetov},
journal= {arXiv preprint arXiv:2006.03130},
year = {2020}
}