Thèses sur le sujet « Source de photons uniques accordable »
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Finazzer, Matteo. « Boîtes quantiques accordées par contrainte mécanique et nanostructures photoniqueslarge bande pour le traitement quantique de l'information ». Electronic Thesis or Diss., Université Grenoble Alpes, 2024. http://www.theses.fr/2024GRALY014.
Texte intégralBright and tunable sources of indistinguishable single photons are key devices for photonic quantum information technologies. Building such a source with a semiconductor quantum dot (QD) requires a “knob” to tune the QD emission wavelength combined with a broadband photonic structure for light extraction. This thesis reports several important steps towards this goal.We first investigate a nanocylinder cavity, a photonic structure that, despites its simplicity, offers a pronounced Purcell acceleration of spontaneous emission over a large spectral bandwidth. We demonstrate the first resonant optical spectroscopy of a QD embedded in a nanopost cavity, by leveraging a cross-polarization scheme that efficiently suppresses stray laser light (collaboration with the group of Richard Warburton). This technique enabled a precise characterization of the optical properties of the emitter.We next demonstrate a tunable single-photon source based on a QD embedded in a tapered photonic wire. In our device, a set of on chip electrodes biased with a DC voltage applies an electrostatic force to the wire. As the wire bends, the resulting mechanical strain changes the bandgap energy of the embedded QDs. We demonstrate both a large increase and a large decrease of the QD emission wavelength by controlling the wire bending direction.With an AC voltage, the above-mentioned actuation scheme can also excite the vibration modes of the nanowire. This capability is interesting in the context of hybrid nanomechanics. In our experiments, we leverage the QD photoluminescence to detect and identify the wire mechanical vibrations. In particular, we evidence a high-order flexural mode that resonates at 190 MHz, a value that exceeds the QD radiative rate. This constitutes an important step towards the spectrally-resolved-sidebands regime.The devices demonstrated in this work open promising prospects for the future developments of quantum photonics and hybrid nanomechanics
Gaignard, Maxime. « Une source efficace de photons uniques et indiscernables ». Electronic Thesis or Diss., Université Grenoble Alpes, 2023. http://www.theses.fr/2023GRALY089.
Texte intégralIn the fields of quantum communications and quantum computing, the transmission of information using single photons guarantees the security of the communication and enables calculations that would be impossible with our "classical" computers. One of the key elements in implementing such protocols is the photon source. It must emit, on demand, one and only one photon with specific quantum properties.The aim of this project is to characterise a source of single and indistinguishable photons, designed and manufactured at CEA-Grenoble, and consisting of an indium arsenide (InAs) semiconductor quantum dot integrated into a gallium arsenide (GaAs) nanocavity. With its low quality factor, the nanocavity enables photons to be extracted efficiently over a wide range of wavelengths (30nm). In addition, thanks to its small mode volume, the spontaneous emission of quantum dots within it can be accelerated by Purcell effect (Purcell factor up to 6).In this manuscript, we first detail the implementation and the optimisation of the experimental setups used to characterise the photons emitted by our sample : microphotoluminescence, radiative lifetime measurement, Hanbury-Brown and Twiss (HBT) experiment and Hong-Ou-Mandel (HOM) experiment. Then, we present the experimental results obtained for photons emitted by two distinct quantum dots : One containing neutral exciton states, and the second, containing a charged exciton state. In order to photo-create these exciton states in the quantum dots, two pulsed optical excitation schemes were implemented: the two-photon resonant excitation of the neutral biexciton, and the phonon-assisted quasi-resonant excitation of the neutral and charged excitons. We present the measurement of the three figures of merit of a single photon source for these two quantum dots : the brightness, the single-photon purity and the indistinguishability of the emitted photons. In a second phase, we will focus on the charged exciton state and measure the profile of its emission line and its autocorrelation function under continuous resonant excitation. These results, achieved within the nano-photonics group of the University of Basel, constitute the first demonstration of continuous excitation on these nanostructures, which is a good surprise given their small size.Finally, we will look at the effects of the application of mechanical stress on the energy separation of the two neutral exciton states, known as the "fine structure splitting" (FSS). During the radiative cascade of the neutral biexciton state, the two photons emitted are entangled in polarisation, and the fidelity of the entanglement depends in particular on the FSS. Here, we will consider a second sample, where the InAs quantum dots are embedded in a GaAs photonic nanowire. By bending the nanowire, mechanical stresses are applied to the quantum dots, which will modify the energy of the exciton states. We will present an experimental study aimed at observing a possible effect on the fine structure splitting.In conclusion, we have developed and optimised various experimental setups for characterising photon sources for applications in the fields of quantum communications and quantum computing. For a first version of these photonic nanostructures, the brightness, the single-photon purity and the indistinguishability of the photons emitted by our quantum dots integrated into nanocavities are very encouraging for the future. The next objectives are to improve the nanocavities and to characterise the decoherence phenomena and the mechanical coupling between the quantum dots and these nanostructures
Cremel, Thibault. « Vers une source de photons uniques opérationnelle à base de nanofils semiconducteurs ». Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAY064/document.
Texte intégralThe recent development of the quantum information theory focuses the interest of the scientific community on single-photon sources. Indeed, these sources can be used for instance for optical quantum computing or quantum cryptography to improve the quantum key distribution performances and avoid eavesdropping. Consequently, it is necessary to have reliable single-photon sources and for realistic applications, the challenge is to get a single-photon source operating up to room temperature.Our group recently demonstrated that by inserting a quantum dot of CdSe in a nanowire of ZnSe, single-photon emission could be obtained up to room temperature. Still, these nanowires had a low quantum yield and were not vertically oriented on the as-grown sample since they were grown along the (001) crystallographic orientation. The interest of vertically oriented nanowires is that they can be coupled to photonic structures to increase their photons collection and their growth is favored on (111)-oriented substrates.In this context, the aim of this PhD work is to develop the growth of vertically oriented ZnSe-CdSe nanowire quantum dots along the (111) crystallographic orientation by molecular beam epitaxy, to study their luminescence up to room temperature for single-photon sources applications, and to couple these nano-objects to photonic structures to increase the photons collection. To reach this goal, we divided this project in three steps.The first step focuses on the development of vertically oriented ZnSe nanowires, passivated with a semiconductor shell of ZnMgSe to enhance their luminescence. In a second step, we demonstrate the possibility to insert CdSe quantum dots in these ZnSe nanowires, using different growth conditions for the quantum dot. The influence of these growth conditions is studied with structural and composition analysis of these nano-objects. Optical studies as a function of the temperature show that these nanowires emit up to room temperature. Moreover, decay-time studies on single nanowire quantum dots reveal that these nanowires are robust and insensitive to non-radiative recombination channels up to 200 K. The third step of this work concerns the enhancement of the light collection from these nano-objects. First, we show that by changing the dielectric environment of the quantum dot, its decay-rate can be increased. Then, we show the possibility to create photonic wires by covering these nanowire quantum dots with a thick dielectric shell. In the light of microphotoluminescence experiments – which show that these photonic wires efficiently increase the photons collection – and simulations, we discuss the interest of the dipole orientation (parallel or perpendicular to the nanowire growth axis) in these structures
Alibart, Olivier. « Source de photons uniques annoncés à 1550nm en optique guidée pour les communications quantiques ». Phd thesis, Université de Nice Sophia-Antipolis, 2004. http://tel.archives-ouvertes.fr/tel-00288268.
Texte intégralL'intervalle de temps entre deux paires successives n'étant pas définit, cette source présente un fonctionnement dit « asynchrone ». Afin de caractériser les performances de ce type de source, nous proposons deux méthodes expérimentales originales. La première repose sur un modèle d'analyse des statistiques des détections dans un montage de type « Hanburry Brown & Twiss » pour remonter aux probabilités d'avoir 0, 1 ou 2 photons, tandis que la seconde est une « version asynchrone » du montage original de « Hanburry Brown & Twiss » pour tracer la fonction de corrélation croisée du second-ordre. Les performances de cette première source de photons uniques aux longueurs d'ondes télécom se situent parmi les meilleures au monde avec une probabilité d'avoir un photon unique à 1550nm de 0,37 accompagnée d'une réduction des événements à deux photons d'un facteur 12 par rapport à une source poissonnienne équivalente.
Couteau, Christophe. « Vers une source de photons uniques indiscernables a l'aide de boites quantiques semiconductrices II-VI ». Phd thesis, Université Paris Sud - Paris XI, 2005. http://tel.archives-ouvertes.fr/tel-00110837.
Texte intégralLa motivation premiere de ces travaux est la recherche d'une source de photons uniques indiscernables adequate pour etre utiliser dans le cadre de l'information quantique, et plus particulierement de l'ordinateur quantique.
Alibart, Olivier. « Source de photons uniques annoncés à 1550 nm en optique guidée pour les communications quantiques ». Nice, 2004. http://www.theses.fr/2004NICE4108.
Texte intégralLong distance quantum communication relies on efficient single photon sources, whose wavelength has to be centered on 1550nm. This thesis reports the realization of a heralded single photon source (HSPS) based on a periodically poled lithium niobate (PPLN) waveguide. The HSPS relies on photon pairs generated by spontaneous parametric down-conversion in a Periodically Poled Lithium Niobate (PPLN) optical waveguide and the idea is to use one of the photons to herald the arrival of the second one. Taking advantage of the guided structure, the photon pairs are collected by a single mode telecom fiber attached to the output of the waveguide. This demonstrates the potential of waveguide technologies for building efficient, stable, and compact sources. The creation time of two successive photons pairs is unknown and the single photons at 1550nm are isolated from others, thanks to the gated detection. Essentially, this is a quantum equivalent of the classical “asynchronous transfer mode”. We point out two means to characterize the efficiency of this type of source. We first investigate an analysis model that allows us to infer the probability of having 0, 1 or 2 photons from the detection on a “Hanbury-Brown & Twiss” type setup, while we build an asynchronous equivalent to the “Hanbury-Brown & Twiss” setup in order to measure the second-order cross-correlation function. This work has lead to the demonstration of having a single photon at with a probability of 0. 37, whereas the multi-photon emission probability is reduced by a factor of 12 compared to weak laser poissonian light sources at equal P1
Couteau, Christophe. « Vers une source de photons uniques indiscernables produits par des boîtes quantiques semiconductrices II-VI ». Paris 11, 2005. https://tel.archives-ouvertes.fr/tel-00110837.
Texte intégralIn the purpose of realising all optical quantum logic gates, this PhD work explores the possibility of using semiconducting quantum dots from II-VI materials as indistinguishable single photon sources. In the general context of quantum information, we tried to set-up the necessary means to study the formation of excitons and multiexcitons in quantum dots. At liquid helium temperature, we realised spectroscopic studies then we studied the statistics of the photons emitted by the dots. With the help of a photon correlation set-up with high temporal resolution, of the order of 100 ps, we demonstrated the photon antibunching effect, typical signature of a single photon source. This pure quantum effect was done in continuous and pulsed regime. Using two spectrometers, we also measured photon cross-correlations between an exciton and its associated biexciton. Once this work was validated, we had to study the indistinguishability of the of the photons emitted by the quantum dots. The indistinguishability being linked to the spectral purity of the emitted photons, optical coherence measurements were necessary to convey. These measurements showed disappointing first results. In parallel, various methods of pumping, of creating carriers in the dots have been studied in order to optimise and increase the coherence length of the photons created by the excitons while recombining. To conclude, possibilities of future experiments or experiments to complete are described
Laurent, Stéphane. « Cavités à bande interdite photonique bidimensionnelle et application à une source de photons uniques indiscernables ». Paris 6, 2006. http://www.theses.fr/2006PA066535.
Texte intégralIsolating a single self-assembled InAs/GaAs quantum dot is a way to produce single photons. Moreover, the successively emitted photons can be indistinguishable if the emission process happens sufficiently fast. This radiative lifetime shortening can be obtained by the use of cavity effects (Purcell effect). In this work we describe the development of two-dimensional photonic band gap cavities for that purpose. A first step was the fabrication of GaAs photonic crystal cavities. Then, inserting a single layer of InAs/GaAs quantum dots in the structure, we managed to isolate a single quantum dot coupled to a single cavity mode, in the weak coupling regime. This system is an indistinguishable single photon source, with a degree of photon indistinguishability of 70 %. The observation of the photon indistinguishability is only possible through a shortening of the emitter lifetime, and indicates that the Purcell effect is more than 25 in this system
Gazzano, Olivier. « Sources brillantes de photons uniques indiscernables et démonstration d'une porte logique quantique ». Phd thesis, Université Paris-Diderot - Paris VII, 2013. http://tel.archives-ouvertes.fr/tel-01006555.
Texte intégralMoreau, Emmanuel. « Étude d'une source solide monomode de photons uniques constituée par une boîte quantique semi-conductrice dans une microcavité optique ». Paris 6, 2002. https://tel.archives-ouvertes.fr/tel-00006244.
Texte intégralHostein, Richard. « Etudes des propriétés optiques et dynamiques des boîtes quantiques InAsP/InP [001] : application à la réalisation de sources de photons uniques et lasers à cristaux photoniques émettant à 1.5 μm ». Paris 6, 2009. https://tel.archives-ouvertes.fr/tel-00439577v2.
Texte intégralJacques, Vincent. « Source de photons uniques et interférences à un seul photon.De l'expérience des fentes d'Young au choix retardé ». Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2007. http://tel.archives-ouvertes.fr/tel-00281163.
Texte intégralDans la première partie, nous étudions la dualité onde-corpuscule pour un photon unique émis par excitation impulsionnelle d'un centre coloré NV individuel dans un nanocristal de diamant. Nous présentons dans un premier temps une expérience d'interférence à un photon réalisée avec un biprisme de Fresnel et par conséquent très proche conceptuellement de l'expérience standard des trous d'Young. Cette expérience permet de discuter de la complémentarité entre interférence et connaissance du chemin suivi par la particule dans l'interféromètre. Pour pénétrer davantage dans les problèmes conceptuels soulevés par la dualité onde-corpuscule, nous décrivons ensuite la réalisation expérimentale de l'expérience de pensée de "choix retardé", qui fût proposée par J. A. Wheeler au début des années soixante-dix.
La deuxième partie du mémoire est dédiée à l'amélioration des performances de sources de photons uniques. Nous décrivons ainsi la mise au point d'une nouvelle source de photons uniques fondée sur l'émission d'un centre coloré individuel à base d'impuretés de nickel dans le diamant, dont les propriétés d'émission sont bien adaptées à la cryptographie quantique en espace libre. Nous avons également mis en oeuvre une technique originale qui améliore de façon significative la photostabilité de molécules individuelles à température ambiante.
Alléaume, Romain. « Réalisation expérimentale de sources de photons uniques, caractérisation et application à la cryptographie quantique ». Phd thesis, Université Pierre et Marie Curie - Paris VI, 2004. http://tel.archives-ouvertes.fr/tel-00008985.
Texte intégralMoreau, Emmanuel. « Etude d'une source solide monomode de photons uniques constituée par une boîte quantique semi-conductrice dans une microcavité optique ». Phd thesis, Université Pierre et Marie Curie - Paris VI, 2002. http://tel.archives-ouvertes.fr/tel-00006244.
Texte intégralBeveratos, Alexios. « Réalisation expérimentale d'une source de photons uniques par fluorescence de centres colorés dans le diamant : application à la cryptographie quantique ». Phd thesis, Paris 11, 2002. http://www.theses.fr/2002PA112236.
Texte intégralSecure key distribution between two persons is a complicated task. In a classical world, it is impossible to guarantee that an eavesdropper doesn't create a copy of the key during the exchange. In 1984 has been proposed a protocol based on the properties of quantum mechanics that assures an unconditionally secure exchange of secret keys. Ideally, the protocol uses single photon sources, the information being coded on the polarisation of the photons. The security is guaranteed by choosing randomly the polarisation base (Linear, Circular). In this context, this work describes the realisation of a single photon source, and it's application to quantum cryptography. A single photon source is obtained by pulsed excitation of a single dipole. The dipole studied in this work, is the NV center in diamond. It is composed of a Nitrogen atom and a Vacancy substituting two carbon atoms. Under continuous excitation the center has been studied with a confocal microscope and an intensity autocorrelation set-up. It has turned out to be a very good candidate for a single photon source since it is easy to manipulate and photostable. Under pulsed excitation, we show that this single photon source has great production efficiency, and a very low number of two-photon pulses. Finally, this source has been used in a quantum cryptography prototype. After a description of the experimental set-ups of the emitter and the receiver, we describe the realisation of a quantum cryptography experiment. The achieved performances show a quantitative advantage in the maximum tolerated tosses, compared to prototypes using faint laser pulses
Au, Thi Huong. « Optimisation et manipulation d'une source de photons uniques par des structures photoniques 2D et 3D à base de matériau polymère à température ambiante ». Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLN046.
Texte intégralThe thesis has been devoted to study the controlled coupling of a colloidal quantum dot (QD) based single photon source (SPS) into multidimensional polymeric photonic structures by using low-one photon absorption (LOPA) direct laser writing (DLW) technique. The thesis consists of three main parts:The first part addresses the characteristic optimization of the CdSe/CdS based SPS. The excitation wavelength dependence of the QDs was investigated. By using 532 nm, only the core of the QD is excited with the suppression of the Auger effects. Thus, this approach allows for obtaining the suppression of fluorescence intermittency and a stable single-photon emission at ambient conditions. In order to obtain the long-term high fluorescence quality of the QDs, we then studied the influence of the local dielectric medium on the optical properties of the QDs. By incorporating the QDs into a photoresist (SU-8), we demonstrated that the polymeric environment not only enables the long-term preservation of the QD with high photostability but also provides us excellent accessibility to fabricate polymeric structures containing SPS.In the second part, the LOPA-based DLW is employed for the coupling of single QD into various photonic structures. Two devices including submicropillar dielectric antenna and 3D membrane bulleye cavity are theoretically and experimentally investigated to enhance the fluorescence emission of the single QD in terms of far-field angular radiation pattern and the spontaneous radiative emission of the emitter.In the third part, the manipulation of SPS is demonstrated by coupling the single QD into multidimensional magneto-photonic structures. With the aid of an external magnetic field, the controllable movement of the coupled QD was performed in the fluidic environment. The position and orientation of the SPS coupled in the structure were manipulated on demand. The mechanical, magnetic and optical properties of the device are investigated showing the multifunctional capabilities of magneto-photonic structures
Darquié, Benoît. « Manipulation d'atomes dans des pièges dipolaires microscopiques et émission contrôlée de photons par une atome unique ». Paris 11, 2005. https://pastel.archives-ouvertes.fr/tel-00011604.
Texte intégralThis work deals with the manipulation of single atoms of rubidium 87 in microscopic optical dipole traps, in order to use them for quantum information processing. The experimental setup is based on a high numerical aperture lens which allows us to focus a beam to the diffraction limit and collects the light emitted by the atoms with a high efficiency. We have characterized the geometry of the potential and the movement of the trapped atoms by measuring oscillation frequencies, and mean energies of the atoms. To demonstrate that our setup is well suited to quantum information processing, we prove its scalability. Using a programmable phase modulator and holographic techniques, we have generated, from a single beam, arrays of micro-dipole traps, each of them being optically addressable. In order to realize two qubit logic gates, we have decided to go towards conditional entanglement. This requires the controlled emission of single photons by each of the atoms, which is obtained after a pulsed excitation. We have developed a new laser system delivering pulses of 4 ns every 200 ns, with a peak power from 1 to 10 W. It allows us to drive coherently the closed transition 5S1/2,F=2,mF=±2 to 5P3/2,F=3,mF=±3. We then observed Rabi oscillations and quantum beats with single atoms. By adjusting the power of the laser source to realize pi-pulses, we obtain a triggered single photon source with a high flux of photons and a weak rate of pulses containing two photons
Bigourdan, Florian. « Nanoantennes plasmoniques ». Thesis, Palaiseau, Institut d'optique théorique et appliquée, 2014. http://www.theses.fr/2014IOTA0020/document.
Texte intégralThe work of this thesis has been devoted to a few applications of antenna concepts for the manipulation of light. In the optical range, surface modes called surface plasmon polaritons take place in the vicinity of metallic antennas, enabling a strong light/matter interaction within highly confined volumes. In order to take advantage of this property, three applications of plasmonic antennas will be investigated. First, in the case of single-photon sources, both theoretical and experimental studies of single-emitters performance when coupled to a planar metallic antenna will be presented. A strategy to enhance its performance will be studied theoretically. Then, in the case of electrical generation of light by inelastic electron tunneling, we will analyse the modification of radiation properties close to a metallic nano-rod. This analysis paves the way towards the design of integrated, compact electrical sources of surface plasmons. Finally, in the case of detecting a weak quantity of molecules, the interaction between an infrared light beam and a sub-nanometric layer of resonant molecules deposited on a nanostructured metallic mirror will be studied
Darquié, Benoît. « MANIPULATION D'ATOMES DANS DES PIÈGES DIPOLAIRES MICROSCOPIQUES ET ÉMISSION CONTRÔLÉE DE PHOTONS PAR UN ATOME UNIQUE ». Phd thesis, Université Paris Sud - Paris XI, 2005. http://tel.archives-ouvertes.fr/tel-00011604.
Texte intégralNous avons caractérisé la géométrie du potentiel et le mouvement des atomes piégés par des mesures de fréquences d'oscillation et d'énergies moyennes.
Pour prouver que ce système est adapté au traitement quantique de l'information, nous montrons que son extensibilité à grande échelle est envisageable. A l'aide d'un modulateur de phase programmable par ordinateur et à partir d'un seul faisceau laser, nous avons généré holographiquement des réseaux de micro-pièges dipolaires pour atomes uniques, chacun des sites étant adressable individuellement.
En vue de réaliser des portes logiques à deux bits quantiques, nous avons choisi de nous orienter vers leur intrication conditionnelle. Celle-ci passe par le contrôle de l'émission de l'atome à l'échelle du photon unique, obtenue à la suite d'une excitation impulsionnelle. Nous avons conçu une chaîne laser délivrant des impulsions nanosecondes. Elle nous assure un contrôle cohérent de la transition fermée (5S1/2, F = 2, mF = 2) vers (5P3/2, F = 3, mF = 3). Nous avons observé des oscillations de Rabi et des battements quantiques sur des atomes uniques. En ajustant la puissance de la chaîne laser pour réaliser des impulsions pi, on obtient une source déclenchable de photons uniques qui présente un flux de hotons important et un faible taux d'impulsions contenant deux photons.
Fain, Bruno. « Analyse des propriétés structurales et électroniques des boîtes quantiques InAs(P)/InP(001) : vers la réalisation d'une source de photons uniques efficace aux longueurs d'onde des télécommunications ». Phd thesis, Ecole Polytechnique X, 2012. http://pastel.archives-ouvertes.fr/pastel-00776836.
Texte intégralFain, Bruno Jean Marie. « Analyse des propriétés structurales et électroniques des boîtes quantiques InAs(P)/InP(001) : vers la réalisation d'une source de photons uniques efficace aux longueurs d'onde des télécommunications ». Palaiseau, Ecole polytechnique, 2012. https://pastel.hal.science/docs/00/77/68/36/PDF/THESE_FAIN.pdf.
Texte intégralWe have studied the growth and the properties of InAsP/InP(001) quantum dots made by metal-organic vapor phase epitaxy for the realization of 1. 55 µm single photon sources. Two complementary approaches, by scanning tunneling microscopy and transmission electron microscopy, have been investigated. On one hand, the study of cleaved quantum dots by scanning tunneling microscopy and spectroscopy, under ultra-high vacuum and at 4K, shows that these nanostructures exhibit up to 12 discretes localized states. Due to the tall height of the cleaved quantum dot, some excited states present a node in the growth direction. Simulation based on finite element method demonstrate that a parabolic potential is relevant to describe the lateral confinement of quantum dots. Tip-induced band bending effects are also studied in cleaved quantum dots, evidencing the contribution of hole states to the tunneling current. On the other hand, the structural properties of self-assembled quantum dots, studied by transmission electron microscopy, are correlated to the growth parameters. The influence of V-elements precursors on the quantum dot density, as well as the exchanges between the quantum dots and the wetting layer, are analyzed. The selective area growth of site-controlled quantum dots in nano-openings whose diameter is smaller than 100 nm is also investigated, in order to obtain a good and reproducible spatial coupling between a quantum dot and an optical microcavity. We show that the quantum dot formation does not rely on the Stranski-Krastanov growth mode, which may allow to control independently the height, the lateral size and the composition of the quantum dots
Ngo, Gia Long. « Manipulation of solid-state single-photon emitters by deterministic coupling into polymer-based photonic structures ». Electronic Thesis or Diss., université Paris-Saclay, 2023. http://www.theses.fr/2023UPAST177.
Texte intégralIn this thesis, we focus on utilizing low-one photon absorption (LOPA) direct laser writing (DLW) to precisely couple colloidal quantum dot (QD)-based single photon emitters (SPEs) into multidimensional polymeric structures. The research is segmented into four parts :The first part presents the optical properties of CdSe/CdS core/shell nanocrystals. We optimize single-photon emission and study the orientation of emitting dipoles within the QDs. We identify our QDs as suitable candidates for integration into photonic structures.The second part details the mechanism of LOPA-based DLW to couple QDs into arbitrary photonic structures based on SU-8 negative photoresist. Next, a particular focus on the circular waveguide resonant grating structure allows us to customize far-field radiation patterns of QD-based SPEs. The findings here contribute to the understanding of optical properties of concentric circular grating structures using low refractive index polymer materials.The third part showcases an approach to optical splitters and combiners using vertical polymeric submicropillar structures operating at the single-photon level. Several architectural configurations are introduced. The results represent advancement toward future quantum optical interconnects based on evanescent wave coupling in vertical configuration.The fourth part explores quantum optical splitters based on a 3D polymeric crossed-arc waveguide structure. This approach provides advantages as it is more mechanically stable than submicropillar structures and has potential for scalability.In conclusion, this thesis provides a framework for deterministically coupling single QDs into polymeric photonic structures using LOPA-based DLW, advancing the field of integrated quantum photonics. Future work could focus on optimizing structures for improved efficiency and scaling the 3D waveguides for more complex configurations
Hostein, Richard. « Étude des propriétés optiques et dynamiques des boîtes quantiques InAsP/InP(001) ; Application à la réalisation de sources de photons uniques et lasers à cristaux photoniques émettant à 1.5 µm ». Phd thesis, Université Pierre et Marie Curie - Paris VI, 2009. http://tel.archives-ouvertes.fr/tel-00439577.
Texte intégralElvira, Antunez David. « Sources à boîtes quantiques semiconductrices pour la nanophotonique et l'information quantique aux longueurs d'onde des télécommunications ». Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00750816.
Texte intégralTreussart, François. « Lumière issue d'émetteurs individuels, applications ». Habilitation à diriger des recherches, Université Pierre et Marie Curie - Paris VI, 2004. http://tel.archives-ouvertes.fr/tel-00011177.
Texte intégralPour pallier l'inévitable photoblanchiment des molécules de colorants, difficilement compatible avec les applications, nous leur avons préféré un centre coloré unique dans un nanocristal de diamant. Ce dernier se comporte du point de vue de sa fluorescence comme un système moléculaire avec l'avantage supplémentaire d'être parfaitement photostable à température ambiante. Nous avons utilisé la source de photons uniques reposant sur ce centre coloré dans une expérience de distribution quantique de clé de cryptage avec une transmission des photons en espace libre. Nous avons montré qu'une telle source permettait encore le partage d'une clé sûre en présence d'une forte atténuation sur la ligne, là où les impulsions laser atténuées ne peuvent plus permettre un tel partage de secret.
Nous décrivons également dans ce mémoire quelques résultats obtenus sur la génération de second harmonique par des nanocristaux organiques et l'utilisation d'un tel signal comme diagnostic du caractère cristallin du nano-objet ainsi détecté. Enfin, nous concluons sur le projet en cours portant sur la manipulation cohérente d'un spin individuel d'un centre coloré du diamant, pour le traitement quantique de l'information.
Nguyen, Hai-Son. « Contrôle optique de l'émission résonnante de boîtes quantiques semiconductrices ». Phd thesis, Université Pierre et Marie Curie - Paris VI, 2011. http://tel.archives-ouvertes.fr/tel-00659615.
Texte intégralNilsson, Jonas. « Génération électrique de lumière intriquée destinée au transfert optique d'information quantique ». Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2013. http://tel.archives-ouvertes.fr/tel-00957826.
Texte intégralMessin, Gaëtan. « Sources de lumière pour l'information quantique ». Habilitation à diriger des recherches, Université Paris Sud - Paris XI, 2008. http://tel.archives-ouvertes.fr/tel-00347157.
Texte intégralL'ensemble de mes activités de recherche s'inscrit dans ce mouvement. Mes travaux ont porté en grande partie sur les sources de photons uniques et les sources de paires de photons, ainsi que leurs applications à la cryptographie quantique, à la téléportation quantique et au calcul quantique. Mes travaux s'ouvrent maintenant sur la suite: variables continues, mémoires quantiques et téléportation d'états non classiques sont probablement les prochaines étapes.
Bin, Ngah Lufti Arif. « Synchronisation toute optique d’un réseau de communication quantique ». Thesis, Nice, 2015. http://www.theses.fr/2015NICE4141/document.
Texte intégralThis manuscript reports the development of fundamental resources for long distance quantum communication based on fibre telecom technology and non-linear optical 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 generate paired photons at telecom wavelength via spontaneous parametric down conversion (SPDC) in periodically poled lithium niobate waveguides (PPLN/W). They rely on type-II and type 0 phase matching, respectively. In the second part, two high quality heralded single photon sources are highlighted. The first one relies on on-chip generation and spatial multiplexing of heralded single photons towards achieving higher bit rates. The second one takes advantage of passive temporal multiplexing of a single SPDC process. 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 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
Gouzien, Élie. « Optique quantique multimode pour le traitement de l'information quantique ». Thesis, Université Côte d'Azur (ComUE), 2019. http://www.theses.fr/2019AZUR4110.
Texte intégralThis thesis studies multimode quantum optics, from generation to detection of light. It focuses on three main parts. Multimode squeezed states generation within cavity is studied. More specifically, we take into account general quadratic Hamiltonian, which allows describing experiments involving arbitrary number of modes and pumps within a medium performing four-wave mixing. We describe a generic approach combining Green functions and symplectic matrix decomposition. This general theory is illustrated on specific cases. First, low-dimensional examples are given. Then, a synchronously pumped optical parametric oscillator (SPOPO) is described and studied; it shows a very distinct behavior from that of the SPOPO using second order non-linearity. This work opens way to the realization of quantum frequency combs with ring micro-resonators engraved on silicon. Single-photon detectors are described taking into account temporal degrees of freedom. We give positive-valued measurement operators describing such detectors including realistic imperfections such as timing-jitter, finite efficiency and dark counts. Use of those operators is illustrated on common quantum optics experiments. Finally, we show how time-resolved measurement allows improving the quality of state generated by single-photon heralded source. In the third part we propose a protocol for generating a hybrid state entangling continuous and discrete variables parts, for which the discrete part is time-bin encoded. This scheme is aanalysed in detail with respect to its resilience to experimental imperfections
Sallen, Gregory. « Spectroscopie optique de boîtes quantiques de CdSe insérées dans des nanofils de ZnSe ». Phd thesis, 2009. http://tel.archives-ouvertes.fr/tel-00362497.
Texte intégralCette étude comprend de la spectroscopie optique standard, où l'on mesure les raies d'émission d'une boite quantique unique en fonction de leur énergie, mais aussi de la spectroscopie résolue en temps, comme des mesures de temps de déclin ou des mesures de corrélation. Les expériences présentées nous ont permis d'étudier la structure fine de l'exciton avec la mesure de l'énergie entre l'exciton noir et l'exciton brillant et le temps de spin flip entre ces deux états. Puis les mesures de corrélation entre chacun des états brillants d'une boîte quantique unique nous ont permis de montrer que nos émetteurs de photons sont des sources de photons uniques de qualité jusqu'à haute température (220 K), et de proposer un modèle décrivant les différents états de cette boîte et leur dynamique de relaxation.
Pour finir, nous nous sommes intéressé à la largeur importante des raies d'émission et aux temps caractéristiques de la diffusion spectrale qui en est responsable. Pour cela, nous avons présenté une nouvelle méthode expérimentale basée sur des mesures de corrélation entre des bandes spectrales de la raie permettant de directement mesurer le temps caractéristique de la diffusion spectrale et d'en étudier le comportement en fonction de différents paramètres comme la puissance d'excitation et la température.