{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,14]],"date-time":"2026-03-14T18:27:47Z","timestamp":1773512867404,"version":"3.50.1"},"reference-count":47,"publisher":"IOP Publishing","issue":"4","license":[{"start":{"date-parts":[[2025,10,8]],"date-time":"2025-10-08T00:00:00Z","timestamp":1759881600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2025,10,8]],"date-time":"2025-10-08T00:00:00Z","timestamp":1759881600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/iopscience.iop.org\/info\/page\/text-and-data-mining"}],"funder":[{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"crossref","award":["KAKENHI JP25K01284"],"award-info":[{"award-number":["KAKENHI JP25K01284"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["iopscience.iop.org"],"crossmark-restriction":false},"short-container-title":["Neuromorph. Comput. Eng."],"published-print":{"date-parts":[[2025,12,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>We propose a novel ultra-high-speed neuron device utilizing a superconductive single flux quantum (SFQ) circuit to realize an ideal rectified linear unit (ReLU) activation function. This circuit generates quantum-accurate voltage output through frequency conversion within the SFQ digital circuit. A significant advantage of this design is its combination of high-speed and ultra-low-power operation with inherent tolerance to device parameter variations. This crucial feature mitigates performance degradation often observed in large-scale neural networks that rely on analog neuron circuits susceptible to characteristic variation of neuron devices. We designed and implemented the proposed neuron circuit using a 10 kA cm<jats:sup>\u22122<\/jats:sup> Nb four-layer 1.0 <jats:italic>\u03bc<\/jats:italic>m fabrication process. Experimental measurements at 4.2 K confirmed correct operation up to approximately 41.2 GHz input. Results from multiple chips successfully demonstrated ideal ReLU input\u2013output characteristics, showcasing both the high-speed nature of the device and the scalability and robustness of our neuron circuits for next-generation artificial neural network hardware.<\/jats:p>","DOI":"10.1088\/2634-4386\/ae0aee","type":"journal-article","created":{"date-parts":[[2025,9,24]],"date-time":"2025-09-24T22:49:17Z","timestamp":1758754157000},"page":"044003","update-policy":"https:\/\/doi.org\/10.1088\/crossmark-policy","source":"Crossref","is-referenced-by-count":2,"title":["High-speed, ultra-low-power, and robust superconductive neuron with ReLU activation"],"prefix":"10.1088","volume":"5","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-9281-847X","authenticated-orcid":true,"given":"Yuto","family":"Ueno","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuki","family":"Hironaka","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nobuyuki","family":"Yoshikawa","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4840-7611","authenticated-orcid":true,"given":"Yuki","family":"Yamanashi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"266","published-online":{"date-parts":[[2025,10,8]]},"reference":[{"key":"nceae0aeebib1","doi-asserted-by":"publisher","first-page":"1629","DOI":"10.1109\/5.58356","type":"journal-article","article-title":"Neuromorphic electronic systems","volume":"78","author":"Mead","year":"1990","journal-title":"Proc. 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