{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,15]],"date-time":"2026-05-15T15:49:01Z","timestamp":1778860141446,"version":"3.51.4"},"reference-count":26,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2023,3,23]],"date-time":"2023-03-23T00:00:00Z","timestamp":1679529600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Institut Quantique (Universit\u00e9 de Sherbrooke)"},{"name":"Institute of Quantum Computing (University of Waterloo)"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We present an integrated single-photon detection device custom designed for quantum key distribution (QKD) with time-bin encoded single photons. We implemented and demonstrated a prototype photon-to-digital converter (PDC) that integrates an 8 \u00d7 8 single-photon avalanche diode (SPAD) array with on-chip digital signal processing built in TSMC 65 nm CMOS. The prototype SPADs are used to validate the QKD functionalities with an array of time-to-digital converters (TDCs) to timestamp and process the photon detection events. The PDC uses window gating to reject noise counts and on-chip processing to sort the photon detections into respective time-bins. The PDC prototype achieved a 22.7 ps RMS timing resolution and demonstrated operation in a time-bin setup with 158 ps time-bins at an optical wavelength of 410 nm. This PDC can therefore be an important building block for a QKD receiver and enables compact and robust time-bin QKD systems with imaging detectors.<\/jats:p>","DOI":"10.3390\/s23073376","type":"journal-article","created":{"date-parts":[[2023,3,23]],"date-time":"2023-03-23T04:37:28Z","timestamp":1679546248000},"page":"3376","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Towards a Multi-Pixel Photon-to-Digital Converter for Time-Bin Quantum Key Distribution"],"prefix":"10.3390","volume":"23","author":[{"given":"Simon","family":"Carrier","sequence":"first","affiliation":[{"name":"D\u00e9partement de G\u00e9nie \u00c9lectrique et de G\u00e9nie Informatique, Universit\u00e9 de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michel","family":"Labrecque-Dias","sequence":"additional","affiliation":[{"name":"D\u00e9partement de G\u00e9nie \u00c9lectrique et de G\u00e9nie Informatique, Universit\u00e9 de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8361-6828","authenticated-orcid":false,"given":"Ramy","family":"Tannous","sequence":"additional","affiliation":[{"name":"Institute for Quantum Computing, Department of Physics & Astronomy, University of Waterloo, Waterloo, ON N2L 3G1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pascal","family":"Gendron","sequence":"additional","affiliation":[{"name":"D\u00e9partement de G\u00e9nie \u00c9lectrique et de G\u00e9nie Informatique, Universit\u00e9 de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6750-7442","authenticated-orcid":false,"given":"Fr\u00e9d\u00e9ric","family":"Nolet","sequence":"additional","affiliation":[{"name":"D\u00e9partement de G\u00e9nie \u00c9lectrique et de G\u00e9nie Informatique, Universit\u00e9 de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nicolas","family":"Roy","sequence":"additional","affiliation":[{"name":"D\u00e9partement de G\u00e9nie \u00c9lectrique et de G\u00e9nie Informatique, Universit\u00e9 de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9270-9193","authenticated-orcid":false,"given":"Tommy","family":"Rossignol","sequence":"additional","affiliation":[{"name":"D\u00e9partement de G\u00e9nie \u00c9lectrique et de G\u00e9nie Informatique, Universit\u00e9 de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6976-6624","authenticated-orcid":false,"given":"Fr\u00e9d\u00e9ric","family":"Vachon","sequence":"additional","affiliation":[{"name":"D\u00e9partement de G\u00e9nie \u00c9lectrique et de G\u00e9nie Informatique, Universit\u00e9 de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Samuel","family":"Parent","sequence":"additional","affiliation":[{"name":"D\u00e9partement de G\u00e9nie \u00c9lectrique et de G\u00e9nie Informatique, Universit\u00e9 de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thomas","family":"Jennewein","sequence":"additional","affiliation":[{"name":"Institute for Quantum Computing, Department of Physics & Astronomy, University of Waterloo, Waterloo, ON N2L 3G1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7857-5056","authenticated-orcid":false,"given":"Serge","family":"Charlebois","sequence":"additional","affiliation":[{"name":"D\u00e9partement de G\u00e9nie \u00c9lectrique et de G\u00e9nie Informatique, Universit\u00e9 de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8327-3842","authenticated-orcid":false,"given":"Jean-Fran\u00e7ois","family":"Pratte","sequence":"additional","affiliation":[{"name":"D\u00e9partement de G\u00e9nie \u00c9lectrique et de G\u00e9nie Informatique, Universit\u00e9 de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1103\/RevModPhys.74.145","article-title":"Quantum cryptography","volume":"74","author":"Gisin","year":"2002","journal-title":"Rev. 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