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All-Optical Synchronization for Quantum Networking Lufti Arif Bin Ngah

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All-Optical Synchronization for Quantum Networking Lufti Arif Bin Ngah All-optical synchronization for quantum networking Lufti Arif Bin Ngah To cite this version: Lufti Arif Bin Ngah. All-optical synchronization for quantum networking. Other [cond-mat.other]. Université Nice Sophia Antipolis, 2015. English. NNT : 2015NICE4141. tel-01292197 HAL Id: tel-01292197 https://tel.archives-ouvertes.fr/tel-01292197 Submitted on 22 Mar 2016 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. UNIVERSITÉ NICE SOPHIA ANTIPOLIS - UFR Sciences ÉCOLE DOCTORALE EN SCIENCES FONDAMENTALES ET APPLIQUÉES Ph.D Dissertation to obtain the title of Docteur en Sciences of Université Nice Sophia Antipolis (UNS), France. Specialization : Physics Presented by Lutfi Arif BIN NGAH All-optical synchronization for quantum networking. Synchronisation toute optique d’un réseau de communication quantique. Defended on December 11, 2015 Jury : Reviewers: Sara Ducci Professor Université Paris Diderot - Paris 7 Rosa Tualle-Brouri Professor Inst. Optique Graduate School, Palaiseau Examinator: John G. Rarity Professor University of Bristol (UK) Advisors: Sébastien Tanzilli DR CNRS Université Nice Sophia Antipolis Virginia D’Auria MCF Université Nice Sophia Antipolis All-optical synchronization for quantum networking. Abstract: This manuscript reports the development of fundamental resources for long distance quantum communication based on fibre telecom technology and non-linear op- tical waveguides. After a general introduction on quantum communication, the thesis is structured along three parts. The first part illustrates the development of two photonic polarization entanglement sources suitable for quantum networking. Both sources allow the generation of paired photons in the telecom C-band of wavelengths via spontaneous parametric down conversion (SPDC) in periodically poled lithium niobate waveguides (PPLN/W). The first source relies on type-II phase matching. In this configuration, two important elements, namely fiber- based walk-off compensation, and deterministic separation of the paired photons using low- loss, dense wavelength division multiplexing (DWDM) filters, are detailed. On the other hand, the second source relies on type-0 SPDC process. Thanks to advanced filtering and interferometric strategies, the produced paires photons can be manipulated at will regarding both their spectral bandwidth and entanglement state, respectively. The source is therefore adapted to a broad variety of quantum photonics applications. In the second part, two high quality heralded single photon sources (HSPS) are high- lighted. The first HSPS relies on on-chip generation and spatial multiplexing of heralded C-band telecom single photons towards achieving higher bit rates. This source relies on the hybridization of two enabling technologies, namely four PPLN/Ws integrated on a single substrate for photon generation by SPDC and laser-written waveguide technologies for routing and multiplexing purposes. Interestingly, such a hybridization has never been demonstrated before. The second HSPS takes advantage of passive temporal multiplexing of a single SPDC process. By taking advantage a 10 GHz repetition rate telecom laser and DWDM filters, combined with an efficient type-0 PPLN/W, an ultra-fast HSPS emitting single photons in the MHz regime at a telecom wavelength is demonstrated. Finally, an all-optical approach towards efficient and accurate synchronization of remote entangled photon pair sources within quantum relay architecture over long distances is presented. This particular synchronization technique highlights the use of ultra-fast ii picosecond pulsed telecom fiber laser, operating at 2.5 GHz repetition rate, acting as a master optical clock, enabling to accurately synchronize the emission of photon pairs in the telecom C-band of wavelengths at two remote locations. This innovative approach is applied for synchronizing two remote PLLN/W based sources operated at 2.5 GHz, and preliminary results on two-photon interference obtained with single photons coming from each source are shown and discussed. Keywords: quantum communication, quantum networking, integrated non-linear optics, quantum optics, PPLN waveguides, polarization entanglement, heralded single photon source, quantum interference, quantum relay. iii Synchronisation toute optique d’un réseau de communication quantique. Résumé : Ce manuscrit expose le développement de ressources fondamentales pour les communications quantiques à longues distances basées sur les technologies des fibres op- tiques télécoms et des guides d’onde optiques non linéaires. Après une introduction générale sur les communications quantiques, cette thèse est structurée en trois parties principales. La première partie illustre le développement de deux sources d’intrication photonique en polarisation adaptées aux réseaux quantiques. Les deux sources permettent la génération de paires de photons dans la bande de longueur d’onde C des télécoms via la conversion paramétrique spontanée (SPDC) dans des guides d’ondes non linéaires intégrés sur niobate de lithium périodiquement polarisé (PPLN/W). La première source s’appuie sur un accord de phase de type-II. Dans cette configuration, sont détaillés deux éléments importants, à savoir la compensation par une fibre optique de la biréfringence induite dans le cristal non linéaire, et la séparation déterministe des paires de photons par le biais de filtres à démul- tiplexage en longueur d’onde (DWDM) à faibles pertes. La deuxième source repose sur un accord de phase de type-0. Dans cette configuration, grâce à des solutions de filtrage et d’interférométrie avancées mises en place après le cristal non linéaire, les photons pro- duits peuvent être manipulés à volonté, aussi bien en terme de largeur spectrale que d’état d’intrication. La source est par conséquent adaptée à une grande variété d’applications en photonique quantique. Dans la seconde partie, sont discutées les réalisations de deux sources de photons uniques annoncés (HSPS) de grande qualité. La première s’appuie sur la génération et le multiplex- age spatial sur puce de photons uniques annoncés dans la bande C des télécoms dans le but d’atteindre des taux de génération accrus. Cette source repose sur l’hybridation de deux technologies clé, à savoir quatre guides d’onde non linéaires intégrés sur une même puce pour la génération des photons et la technologie d’écriture de guides d’onde par laser pour le routage et le multiplexage. Notons que ce type d’hybridation n’avait jamais été démontré auparavant. La seconde HSPS exploite le multiplexage temporel passif d’un pro- cessus SPDC unique. En effet, l’utilisation d’un laser télécom cadencé à 10 GHz et de filtres DWDM, combinés à un guide d’onde non linaire de type-0, a permis d’implémenter une source ultra-rapide émettant des photons uniques à des cadences de l’ordre de quelques iv MHz dans la bande C des télécoms. Enfin, nous présentons une approche tou-optique visant la synchronisation efficace et précise de sources distantes de paires de photons intriqués, agencées selon une architecture de type relais quantique distribué. Cette technique de synchronisation innonvante met en avant l’utilisation d’un laser télécom impulsionnel picoseconde cadencé à 2,5 GHz en tant qu’horloge optique de référence. Cette horloge autorise la synchronisation précise de l’émission de paires de photons dans la bande C des télécoms en deux lieux distants. Cette approche est appliquée à la synchronisation de deux sources basée sur des guides d’onde non linéaires opérant à 2,5 GHz. À ce titre, des résultats préliminaires d’interférence à deux photons obtenue à partir de photons uniques en provenance de chacune de ces sources sont montrés et discutés. Mots clés : communication quantique, réseaux quantiques, optique intégrée, op- tique quantique, guides PPLN, intrication en polarisation, source de photons uniques annoncés, interférence quantique, relais quantique. Acknowledgements First and foremost I would like to express my special appreciation and my most heartfelt thanks to my main thesis supervisor, Sébastien Tanzilli for being my mentor and also a very good friend. I wholeheartedly appreciate everything you’ve done for me, everything. To my thesis co-director, Virginia D’Auria, I will never forget the time we spent working together in the CONNEQT lab. I will always remember your kindness, and our tea time together with Bruno! Olivier Alibart, you taught me a lot of things, in the lab, as well as in Sydney. Laurent Labonté, I really appreciate your kindness and all your helps. Not to forget Dan Ostrowsky for all the hot sauces, and the lunches at your wonderful place. Thanks Dan. To Anders Kastberg who also happens to be a Chelsea fan like me, I appreciate all the discussions and insights from you. To Eric Picholle, I still remember the late evenings we spent in the lab, preparing me for the thesis defense. Séb, Virginia, Olivier, Laurent, Anders and Eric, thank you very much. All of you have been there to support me and words cannot express how grateful I am to you guys. I would also like to thank the members of my dissertation
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