{"title":"Photon Number Splitting Attack – Proposal and Analysis of an Experimental Scheme","authors":"Ariel Ashkenazy, Yuval Idan, Dor Korn, Dror Fixler, Barak Dayan, Eliahu Cohen","doi":"10.1002/qute.202300437","DOIUrl":"10.1002/qute.202300437","url":null,"abstract":"<p>Photon-number-splitting (PNS) is a well-known theoretical attack on quantum key distribution (QKD) protocols that employ weak coherent states produced by attenuated laser pulses. However, beyond the fact that it has not yet been demonstrated experimentally, its plausibility and effect on quantum bit error rate are questioned. In this work, an experimental scheme is presented for PNS attack employing demonstrated technological capabilities, specifically a single-photon Raman interaction (SPRINT) in a cavity-enhanced three-level atomic system. Several aspects of the proposed implementation are addressed, analytically and simulatively, and the eavesdropper's information gain by the attack is calculated. Furthermore, it is analytically shown that the scheme results in a small (yet non-zero) quantum bit error rate, and a comparison to purely theoretical analyses in the literature is presented. It is believed that the inherent nonlinearity of the PNS attack unavoidably affects the optical modes sent to the receiver, and accordingly will always result in some error rate.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qute.202300437","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140802663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Soumya Chakraborty, Pooja Yadav, Daniel Moraru, Arup Samanta
{"title":"Transport Spectroscopy of Donor/Quantum Dot Interactive System in Silicon Nano-Transistors","authors":"Soumya Chakraborty, Pooja Yadav, Daniel Moraru, Arup Samanta","doi":"10.1002/qute.202400011","DOIUrl":"10.1002/qute.202400011","url":null,"abstract":"<p>Donor-atom-based nano-devices in silicon represent a breakthrough for individual control of electrons at atomic scale. Here, a finite-bias characterization of electrical transport through such a device, fabricated on a silicon-on-insulator (SOI) wafer with low phosphorus (P) doping, is presented. In this device, multiple quasi-periodic current peaks are observed at low temperatures in the electrical transfer characteristics. Such behavior of the transport characteristics is generally observed in devices having high doping concentration or with selective doping in the channel region to form a multi-donor cluster quantum dot. However, in the present device donor–cluster formation is highly improbable owing to low doping concentration. The observed electrical transport characteristics of the device are explained with a model of two non-interacting donors coupled in series with an unintentionally larger quantum dot, likely formed within the channel due to roughness. Theoretical simulation is also presented here for such a circuit supporting the experimental observations.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140660144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Tight Upper Bound for the Maximal Expectation Value of the \u0000 \u0000 N\u0000 $N$\u0000 -Partite Generalized Svetlichny Operator","authors":"Youwang Xiao, Zong Wang, Wen-Na Zhao, Ming Li","doi":"10.1002/qute.202400101","DOIUrl":"10.1002/qute.202400101","url":null,"abstract":"<p>Genuine multipartite non-locality is not only of fundamental interest but also serves as an important resource for quantum information theory. The <span></span><math>\u0000 <semantics>\u0000 <mi>N</mi>\u0000 <annotation>$N$</annotation>\u0000 </semantics></math>-partite scenario and provide an analytical upper bound on the maximal expectation value of the generalized Svetlichny inequality achieved by an arbitrary <span></span><math>\u0000 <semantics>\u0000 <mi>N</mi>\u0000 <annotation>$N$</annotation>\u0000 </semantics></math>-qubit system is considered. Furthermore, the constraints on quantum states for which the upper bound is tight are also presented and illustrated by noisy generalized Greenberger-Horne-Zeilinger states. Especially, the new techniques proposed to derive the upper bound allow more insights into the structure of the generalized Svetlichny operator and enable us to systematically investigate the relevant properties. As an operational approach, the variation of the correlation matrix defined makes it more convenient to search for suitable unit vectors that satisfy the tightness conditions. Finally, the results give feasible experimental implementations in detecting the genuine multipartite non-locality and can potentially be applied to other quantum information processing tasks.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140635778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}