[{"abstract":[{"text":"<jats:title>Abstract</jats:title><jats:p>The nonorthogonality of coherent states is a fundamental property which prevents them from being perfectly and deterministically discriminated. Here, we present an experimentally feasible protocol for the probabilistic orthogonalisation of a pair of coherent states, independent of their amplitude and phase. In contrast to unambiguous state discrimination, a successful operation of our protocol is heralded without measuring the states. As such, they remain suitable for further manipulation and the obtained orthogonal states serve as a discretevariable basis. Therefore, our protocol doubles as a simple continuous-to-discrete variable converter, which may find application in hybrid continuous-discrete quantum information processing protocols.</jats:p>","lang":"eng"}],"status":"public","type":"journal_article","publication":"Quantum Measurements and Quantum Metrology","language":[{"iso":"eng"}],"_id":"16101","user_id":"49683","department":[{"_id":"15"}],"year":"2018","citation":{"mla":"Kruse, Regina, et al. “Heralded Orthogonalisation of Coherent States and Their Conversion to Discrete-Variable Superpositions.” <i>Quantum Measurements and Quantum Metrology</i>, vol. 4, no. 1, 2018, doi:<a href=\"https://doi.org/10.1515/qmetro-2017-0005\">10.1515/qmetro-2017-0005</a>.","bibtex":"@article{Kruse_Silberhorn_Bartley_2018, title={Heralded orthogonalisation of coherent states and their conversion to discrete-variable superpositions}, volume={4}, DOI={<a href=\"https://doi.org/10.1515/qmetro-2017-0005\">10.1515/qmetro-2017-0005</a>}, number={1}, journal={Quantum Measurements and Quantum Metrology}, author={Kruse, Regina and Silberhorn, Christine and Bartley, Tim}, year={2018} }","short":"R. Kruse, C. Silberhorn, T. Bartley, Quantum Measurements and Quantum Metrology 4 (2018).","apa":"Kruse, R., Silberhorn, C., &#38; Bartley, T. (2018). Heralded orthogonalisation of coherent states and their conversion to discrete-variable superpositions. <i>Quantum Measurements and Quantum Metrology</i>, <i>4</i>(1). <a href=\"https://doi.org/10.1515/qmetro-2017-0005\">https://doi.org/10.1515/qmetro-2017-0005</a>","chicago":"Kruse, Regina, Christine Silberhorn, and Tim Bartley. “Heralded Orthogonalisation of Coherent States and Their Conversion to Discrete-Variable Superpositions.” <i>Quantum Measurements and Quantum Metrology</i> 4, no. 1 (2018). <a href=\"https://doi.org/10.1515/qmetro-2017-0005\">https://doi.org/10.1515/qmetro-2017-0005</a>.","ieee":"R. Kruse, C. Silberhorn, and T. Bartley, “Heralded orthogonalisation of coherent states and their conversion to discrete-variable superpositions,” <i>Quantum Measurements and Quantum Metrology</i>, vol. 4, no. 1, 2018.","ama":"Kruse R, Silberhorn C, Bartley T. Heralded orthogonalisation of coherent states and their conversion to discrete-variable superpositions. <i>Quantum Measurements and Quantum Metrology</i>. 2018;4(1). doi:<a href=\"https://doi.org/10.1515/qmetro-2017-0005\">10.1515/qmetro-2017-0005</a>"},"intvolume":"         4","publication_status":"published","publication_identifier":{"issn":["2299-114X"]},"issue":"1","title":"Heralded orthogonalisation of coherent states and their conversion to discrete-variable superpositions","doi":"10.1515/qmetro-2017-0005","date_updated":"2022-01-06T06:52:43Z","date_created":"2020-02-26T14:51:18Z","author":[{"full_name":"Kruse, Regina","last_name":"Kruse","first_name":"Regina"},{"id":"26263","full_name":"Silberhorn, Christine","last_name":"Silberhorn","first_name":"Christine"},{"first_name":"Tim","full_name":"Bartley, Tim","id":"49683","last_name":"Bartley"}],"volume":4},{"date_updated":"2020-02-26T14:38:03Z","date_created":"2019-05-17T14:08:35Z","author":[{"last_name":"Barbieri","full_name":"Barbieri, Marco","first_name":"Marco"},{"first_name":"Animesh","full_name":"Datta, Animesh","last_name":"Datta"},{"last_name":"Bartley","full_name":"Bartley, Tim","id":"49683","first_name":"Tim"},{"full_name":"Jin, Xian-Min","last_name":"Jin","first_name":"Xian-Min"},{"first_name":"W. Steven","last_name":"Kolthammer","full_name":"Kolthammer, W. Steven"},{"first_name":"Ian A.","full_name":"Walmsley, Ian A.","last_name":"Walmsley"}],"title":"Quantum enhanced estimation of optical detector efficiencies","doi":"10.1515/qmetro-2016-0002","publication_identifier":{"issn":["2299-114X"]},"publication_status":"published","year":"2016","citation":{"apa":"Barbieri, M., Datta, A., Bartley, T., Jin, X.-M., Kolthammer, W. S., &#38; Walmsley, I. A. (2016). Quantum enhanced estimation of optical detector efficiencies. <i>Quantum Measurements and Quantum Metrology</i>. <a href=\"https://doi.org/10.1515/qmetro-2016-0002\">https://doi.org/10.1515/qmetro-2016-0002</a>","mla":"Barbieri, Marco, et al. “Quantum Enhanced Estimation of Optical Detector Efficiencies.” <i>Quantum Measurements and Quantum Metrology</i>, 2016, doi:<a href=\"https://doi.org/10.1515/qmetro-2016-0002\">10.1515/qmetro-2016-0002</a>.","bibtex":"@article{Barbieri_Datta_Bartley_Jin_Kolthammer_Walmsley_2016, title={Quantum enhanced estimation of optical detector efficiencies}, DOI={<a href=\"https://doi.org/10.1515/qmetro-2016-0002\">10.1515/qmetro-2016-0002</a>}, journal={Quantum Measurements and Quantum Metrology}, author={Barbieri, Marco and Datta, Animesh and Bartley, Tim and Jin, Xian-Min and Kolthammer, W. Steven and Walmsley, Ian A.}, year={2016} }","short":"M. Barbieri, A. Datta, T. Bartley, X.-M. Jin, W.S. Kolthammer, I.A. Walmsley, Quantum Measurements and Quantum Metrology (2016).","chicago":"Barbieri, Marco, Animesh Datta, Tim Bartley, Xian-Min Jin, W. Steven Kolthammer, and Ian A. Walmsley. “Quantum Enhanced Estimation of Optical Detector Efficiencies.” <i>Quantum Measurements and Quantum Metrology</i>, 2016. <a href=\"https://doi.org/10.1515/qmetro-2016-0002\">https://doi.org/10.1515/qmetro-2016-0002</a>.","ieee":"M. Barbieri, A. Datta, T. Bartley, X.-M. Jin, W. S. Kolthammer, and I. A. Walmsley, “Quantum enhanced estimation of optical detector efficiencies,” <i>Quantum Measurements and Quantum Metrology</i>, 2016.","ama":"Barbieri M, Datta A, Bartley T, Jin X-M, Kolthammer WS, Walmsley IA. Quantum enhanced estimation of optical detector efficiencies. <i>Quantum Measurements and Quantum Metrology</i>. 2016. doi:<a href=\"https://doi.org/10.1515/qmetro-2016-0002\">10.1515/qmetro-2016-0002</a>"},"_id":"9836","department":[{"_id":"15"}],"user_id":"49683","language":[{"iso":"eng"}],"publication":"Quantum Measurements and Quantum Metrology","type":"journal_article","abstract":[{"text":"<jats:title>Abstract</jats:title><jats:p>Quantum mechanics establishes the ultimate limit to the scaling of the precision on any parameter, by identifying optimal probe states and measurements. While this paradigm is, at least in principle, adequate for the metrology of quantum channels involving the estimation of phase and loss parameters, we show that estimating the loss parameters associated with a quantum channel and a realistic quantum detector are fundamentally different. While Fock states are provably optimal for the former, we identify a crossover in the nature of the optimal probe state for estimating detector imperfections as a function of the loss parameter using Fisher information as a benchmark. We provide theoretical results for on-off and homodyne detectors, the most widely used detectors in quantum photonics technologies, when using Fock states and coherent states as probes.</jats:p>","lang":"eng"}],"status":"public"},{"_id":"16108","user_id":"49683","department":[{"_id":"15"}],"extern":"1","language":[{"iso":"eng"}],"type":"journal_article","publication":"Quantum Measurements and Quantum Metrology","status":"public","date_updated":"2022-01-06T06:52:43Z","date_created":"2020-02-26T15:03:56Z","author":[{"first_name":"Mihai","full_name":"Vidrighin, Mihai","last_name":"Vidrighin"},{"first_name":"Tim","id":"49683","full_name":"Bartley, Tim","last_name":"Bartley"},{"full_name":"Donati, Gaia","last_name":"Donati","first_name":"Gaia"},{"last_name":"Jin","full_name":"Jin, Xian-Min","first_name":"Xian-Min"},{"first_name":"Marco","full_name":"Barbieri, Marco","last_name":"Barbieri"},{"first_name":"W. Steven","last_name":"Kolthammer","full_name":"Kolthammer, W. Steven"},{"full_name":"Datta, Animesh","last_name":"Datta","first_name":"Animesh"},{"first_name":"Ian A.","full_name":"Walmsley, Ian A.","last_name":"Walmsley"}],"title":"Requirements for two-source entanglement concentration","doi":"10.2478/qmetro-2013-0002","publication_status":"published","publication_identifier":{"issn":["2299-114X"]},"year":"2013","citation":{"bibtex":"@article{Vidrighin_Bartley_Donati_Jin_Barbieri_Kolthammer_Datta_Walmsley_2013, title={Requirements for two-source entanglement concentration}, DOI={<a href=\"https://doi.org/10.2478/qmetro-2013-0002\">10.2478/qmetro-2013-0002</a>}, journal={Quantum Measurements and Quantum Metrology}, author={Vidrighin, Mihai and Bartley, Tim and Donati, Gaia and Jin, Xian-Min and Barbieri, Marco and Kolthammer, W. Steven and Datta, Animesh and Walmsley, Ian A.}, year={2013} }","short":"M. Vidrighin, T. Bartley, G. Donati, X.-M. Jin, M. Barbieri, W.S. Kolthammer, A. Datta, I.A. Walmsley, Quantum Measurements and Quantum Metrology (2013).","mla":"Vidrighin, Mihai, et al. “Requirements for Two-Source Entanglement Concentration.” <i>Quantum Measurements and Quantum Metrology</i>, 2013, doi:<a href=\"https://doi.org/10.2478/qmetro-2013-0002\">10.2478/qmetro-2013-0002</a>.","apa":"Vidrighin, M., Bartley, T., Donati, G., Jin, X.-M., Barbieri, M., Kolthammer, W. S., … Walmsley, I. A. (2013). Requirements for two-source entanglement concentration. <i>Quantum Measurements and Quantum Metrology</i>. <a href=\"https://doi.org/10.2478/qmetro-2013-0002\">https://doi.org/10.2478/qmetro-2013-0002</a>","chicago":"Vidrighin, Mihai, Tim Bartley, Gaia Donati, Xian-Min Jin, Marco Barbieri, W. Steven Kolthammer, Animesh Datta, and Ian A. Walmsley. “Requirements for Two-Source Entanglement Concentration.” <i>Quantum Measurements and Quantum Metrology</i>, 2013. <a href=\"https://doi.org/10.2478/qmetro-2013-0002\">https://doi.org/10.2478/qmetro-2013-0002</a>.","ieee":"M. Vidrighin <i>et al.</i>, “Requirements for two-source entanglement concentration,” <i>Quantum Measurements and Quantum Metrology</i>, 2013.","ama":"Vidrighin M, Bartley T, Donati G, et al. Requirements for two-source entanglement concentration. <i>Quantum Measurements and Quantum Metrology</i>. 2013. doi:<a href=\"https://doi.org/10.2478/qmetro-2013-0002\">10.2478/qmetro-2013-0002</a>"}}]