{"id":2402,"date":"2025-02-20T18:10:44","date_gmt":"2025-02-20T16:10:44","guid":{"rendered":"https:\/\/webs.uab.cat\/giq\/?post_type=seminar&#038;p=2402"},"modified":"2025-03-18T18:11:33","modified_gmt":"2025-03-18T16:11:33","slug":"measurement-device-independent-randomness-source-based-on-mode-competition-in-a-gain-switched-vcsel","status":"publish","type":"seminar","link":"https:\/\/webs.uab.cat\/giq\/seminar\/measurement-device-independent-randomness-source-based-on-mode-competition-in-a-gain-switched-vcsel\/","title":{"rendered":"Measurement-device-independent randomness source based on mode-competition in a gain-switched VCSEL"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\"><em>In this work, we prove the security of a randomness generation protocol based on operating a vertical-cavity surface-emitting laser in a gain-switching manner. The source of entropy is the random alternation between orthogonal polarization modes induced by spontaneous emission inside the laser cavity. Our prepare-and-measure protocol features two trusted preparations and a single uncharacterized and untrusted measurement. First, using semidefinite programming techniques, we upper bound the maximum probability for an attacker to guess the outcome for a single use of the device. Then, combined with the entropy accumulation theorem and with a study of finite-size effects, we use this result to lower bound the minimum amount of secure smooth min-entropy that can be generated without making assumptions of an\u00a0i.i.d.\u00a0regime. We\u00a0are able to\u00a0certify positive entropy rates in the finite-size regime for as low as 7E4 rounds.<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>In this work, we prove the security of a randomness generation protocol based on operating a vertical-cavity surface-emitting laser in a gain-switching manner. The source of entropy is the random alternation between orthogonal polarization modes induced by spontaneous emission inside the laser cavity. Our prepare-and-measure protocol features two trusted preparations and a single uncharacterized and [&hellip;]<\/p>\n","protected":false},"author":2605,"featured_media":0,"template":"","class_list":["post-2402","seminar","type-seminar","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/webs.uab.cat\/giq\/wp-json\/wp\/v2\/seminar\/2402","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/webs.uab.cat\/giq\/wp-json\/wp\/v2\/seminar"}],"about":[{"href":"https:\/\/webs.uab.cat\/giq\/wp-json\/wp\/v2\/types\/seminar"}],"author":[{"embeddable":true,"href":"https:\/\/webs.uab.cat\/giq\/wp-json\/wp\/v2\/users\/2605"}],"wp:attachment":[{"href":"https:\/\/webs.uab.cat\/giq\/wp-json\/wp\/v2\/media?parent=2402"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}