{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:06:49Z","timestamp":1760234809201,"version":"build-2065373602"},"reference-count":33,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,6,25]],"date-time":"2021-06-25T00:00:00Z","timestamp":1624579200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100013168","name":"Istituto Nazionale di Fisica Nucleare","doi-asserted-by":"publisher","award":["FEEL"],"award-info":[{"award-number":["FEEL"]}],"id":[{"id":"10.13039\/501100013168","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Evidence is reported that topological effects in graph-shaped arrays of superconducting islands can condition superconducting energy gap and transition temperature. The carriers giving rise to the new phase are couples of electrons (Cooper pairs) which, in the superconducting state, behave as predicted for bosons in our structures. The presented results have been obtained both on star and double comb-shaped arrays and the coupling between the islands is provided by Josephson junctions whose potential can be tuned by external magnetic field or temperature. Our peculiar technique for probing distribution on the islands is such that the hopping of bosons between the different islands occurs because their thermal energy is of the same order of the Josephson coupling energy between the islands. Both for star and double comb graph topologies the results are in qualitative and quantitative agreement with theoretical predictions.<\/jats:p>","DOI":"10.3390\/e23070811","type":"journal-article","created":{"date-parts":[[2021,6,25]],"date-time":"2021-06-25T11:07:40Z","timestamp":1624619260000},"page":"811","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Josephson Currents and Gap Enhancement in Graph Arrays of Superconductive Islands"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2110-9104","authenticated-orcid":false,"given":"Massimiliano","family":"Lucci","sequence":"first","affiliation":[{"name":"Dipartimento di Fisica and <i>MINAS<\/i> Lab, Universit\u00e0 di Roma \u201cTor Vergata\u201d, 00133 Roma, Italy"},{"name":"Istituto Nazionale di Fisica Nucleare, Sezione di Roma \u201cTor Vergata\u201d, 00133 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Davide","family":"Cassi","sequence":"additional","affiliation":[{"name":"Dipartimento di Scienze Matematiche, Fisiche ed Informatiche, Universit\u00e0 di Parma, 43124 Parma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4858-3714","authenticated-orcid":false,"given":"Vittorio","family":"Merlo","sequence":"additional","affiliation":[{"name":"Dipartimento di Fisica and <i>MINAS<\/i> Lab, Universit\u00e0 di Roma \u201cTor Vergata\u201d, 00133 Roma, Italy"},{"name":"Istituto Nazionale di Fisica Nucleare, Sezione di Roma \u201cTor Vergata\u201d, 00133 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9431-6265","authenticated-orcid":false,"given":"Roberto","family":"Russo","sequence":"additional","affiliation":[{"name":"Consiglio Nazionale delle Ricerche, CNR-ISASI, Via Castellino 111, 80131 Napoli, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1767-0724","authenticated-orcid":false,"given":"Gaetano","family":"Salina","sequence":"additional","affiliation":[{"name":"Istituto Nazionale di Fisica Nucleare, Sezione di Roma \u201cTor Vergata\u201d, 00133 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Matteo","family":"Cirillo","sequence":"additional","affiliation":[{"name":"Dipartimento di Fisica and <i>MINAS<\/i> Lab, Universit\u00e0 di Roma \u201cTor Vergata\u201d, 00133 Roma, Italy"},{"name":"Istituto Nazionale di Fisica Nucleare, Sezione di Roma \u201cTor Vergata\u201d, 00133 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,25]]},"reference":[{"key":"ref_1","unstructured":"Bhattacharjee, S.M., Mahan, M.J., and Bandyopadhyay, A. 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