Novel wave phenomena in two- and three-dimensional (2D and 3D) phononic crystals were investigated experimentally using ultrasonic techniques. Resonant tunneling of ultrasonic waves was successfully observed for the first time by measuring the transmission of ultrasound pulses through a double barrier consisting of two 3D phononic crystals separated by a cavity. This effect is the classical analogue of resonant tunneling of a quantum mechanical particle through a double potential barrier, in which transmission reaches unity at resonant frequencies. For phononic crystals, the tunneling peak was found to be less than unity, an effect that was explained by absorption. The dynamics of resonant tunneling was explored by measuring the group velocities of the ultrasonic pulses. Very slow and very fast velocities were found at frequencies close to and at the resonance, respectively. These extreme values are less than the speed of sound in air and greater than the speed of sound in any of the crystal’s constituent materials. Negative refraction and focusing effects in 2D phononic crystals were also observed. Negative refraction of ultrasound was demonstrated unambiguously in a prism-shaped 2D crystal at frequencies in the 2nd pass band where the wave vector and group velocity are opposite. The Multiple Scattering Theory and Snell’s law allowed theoretical predictions of the refraction angles. Excellent agreement was found between theory and experiment. The negative refraction experiments revealed a mechanism that can be used to focus ultrasound using a flat phononic crystal, and experiments to demonstrate the focusing of ultrasound emitted by several point sources were successfully carried out. The importance of using phononic crystals with circular equifrequency contours, as well as matching the size of the contours inside and outside the crystal, was established. Both conditions were satisfied by a flat phononic crystal of steel rods, in which the liquid inside the crystal (methanol) was different from the outside medium (water). The possibility of achieving subwavelength resolution using this phononic crystal was investigated with a subwavelength line source (a miniature strip-shaped transducer, approximately lambda/5 wide, where lambda is sound wavelength in water). A resolution of 0.55lambda was found, which is just above the diffraction limit lambda/2.

Quantum technologies are transitioning from the laboratories of academia to industry and the commercial sector. Scaling the utilization of such systems will require optical quantum networks capable of interconnecting quantum nodes, as well as transmitting and receiving quantum states without loss of entanglement. In order to enable such quantum networks and pave the way for a quantum internet, “quantum state transceivers” (QSTs) must be developed. QSTs will be systems with mixed classical and quantum capabilities, and are ideally implemented as quantum-capable “systems-on-chip” (QSoCs) to allow for cost and complexity scaling. In this work, we leverage electronics-photonics monolithic integration in silicon CMOS technology to develop a new class of electronic-photonic systems-on-chip with quantum photonic functions -- electronic-photonic quantum systems-on-chip (epQSoCs). As a first demonstrator of such a “quantum” electronics-photonics platform, we implement a single-chip “wall-plug”, high efficiency photon pair source. We demonstrate a first example system-on-chip, as well as a basic building block component that can be utilized in future, more complex electronic-photonic QSoCs, by analogy to the hierarchical design of classical electronics chips, comprising of smaller component building blocks (so called IP blocks). Additionally, we investigate a novel radiation-free dielectric nanocavity with all-evanescent confinement based on perfect mode-matching and minimal use of negative permittivity, with potential for applications in future generations of photonic circuits. / 2024-05-24T00:00:00Z

Guided mode resonant (GMR) structures are optical devices that consist of a planar waveguide with a periodic structure either imbedded in or on the surface of the structure. The resonance anomaly in GMR structures has many applications as dielectric mirrors, tunable devices, sensors,and narrow spectral band reflection filters. A desirable response from a resonant grating filter normally includes a nearly 100% narrowband resonant spectral reflection (transmission), and a broad angular acceptance at either normal incidence or an oblique angle of incidence. This dissertation is a detailed study of the unique nature of the resonance anomaly in GMR structures with two-dimensional (2-D) periodic perturbation. Clear understanding of the resonance phenomenon is developed and novel 2-D GMR structures are proposed to significantly improve the performance of narrow spectral filters. In 2-D grating diffraction, each diffracted order inherently propagates in its distinct diffraction plane. This allows for coupled polarization dependent resonant leaky modes with one in each diffraction plane. The nature of the interaction between these non-collinear guides and its impact on spectral and angular response of GMR devices is investigated and quantified for 2-D structures with rectangular and hexagonal grids. Based on the developed understanding of the underlying phenomenon, novel GMR devices are proposed and analyzed. A novel controllable multi-line guided mode resonant (GMR) filter is proposed. The separation of spectral wavelength resonances supported by a two-dimensional GMR structure can be coarse or fine depending on the physical dimensions of the structure and not the material properties. Multiple resonances are produced by weakly guided modes individually propagating along multiple planes of diffraction. Controllable two-line and three-line narrow-band reflection filter designs with spectral separation from a few up to hundreds of nanometers are exhibited using rectangular-lattice and hexagonal-lattice grating GMR structures, respectively. Broadening of the angular response of narrow band two-dimension guided mode resonant spectral filters, while maintaining a narrow spectral response, is investigated. The angular response is broadened by coupling the diffracted orders into multiple fundamental guided resonant modes. These guided modes have the same propagation constant but propagating in different planes inherent in multiple planes of diffraction of the 2-D gratings. The propagation constants of the guided resonant modes are determined from the physical dimensions of the grating (periodicity and duty cycle) and the incident direction. A five-fold improvement in the angular tolerance is achieved using a grating with strong second Bragg diffraction in order to produce a crossed diffraction. A novel dual grating structure with a second grating located on the substrate side is proposed to further broaden the angular tolerance of the spectral filter without degrading its spectral response. This strong second Bragg backward diffraction from the substrate grating causes two successive resonant bands to merge producing a resonance with symmetric broad angular response.

Reliability and sensitive information protection are critical aspects of integrated circuits. A novel technique using near-field evanescent wave coupling from two subwavelength gratings (SWGs), with the input laser source delivered through an optical fiber is presented for tamper evidence of electronic components. The first grating of the pair of coupled subwavelength gratings (CSWGs) was milled directly on the output facet of the silica fiber using focused ion beam (FIB) etching. The second grating was patterned using e-beam lithography and etched into a glass substrate using reactive ion etching (RIE). The slightest intrusion attempt would separate the CSWGs and eliminate near-field coupling between the gratings. Tampering, therefore, would become evident. Computer simulations guided the design for optimal operation of the security solution. The physical dimensions of the SWGs, i.e. period and thickness, were optimized, for a 650 nm illuminating wavelength. The optimal dimensions resulted in a 560 nm grating period for the first grating etched in the silica optical fiber and 420 nm for the second grating etched in borosilicate glass. The incident light beam had a half-width at half-maximum (HWHM) of at least 7 µm to allow discernible higher transmission orders, and a HWHM of 28 µm for minimum noise. The minimum number of individual grating lines present on the optical fiber facet was identified as 15 lines. Grating rotation due to the cylindrical geometry of the fiber resulted in a rotation of the far-field pattern, corresponding to the rotation angle of moiré fringes. With the goal of later adding authentication to tamper evidence, the concept of CSWGs signature was also modeled by introducing random and planned variations in the glass grating. The fiber was placed on a stage supported by a nanomanipulator, which permitted three-dimensional displacement while maintaining the fiber tip normal to the surface of the glass substrate. A 650 nm diode laser was fixed to a translation mount that transmitted the light source through the optical fiber, and the output intensity was measured using a silicon photodiode. The evanescent wave coupling output results for the CSWGs were measured and compared to the simulation results.

Dans le domaine de l'imagerie infrarouge, on distingue deux types de technologies : les détecteurs refroidis, coûteux et très performants, et les détecteurs thermiques, bas coût et moins encombrants. Dans les deux cas le système optique associé au détecteur représente une part importante du coût total du fait de la production unitaire de lentilles et du besoin en une résolution de plus en plus importante pour suivre la diminution du pas pixel et l'augmentation du format des détecteurs. Dès lors il est intéressant d'explorer des solutions pour diminuer le coût et l'encombrement du système optique tout en maintenant ou en améliorant les performances optiques. Dans ce contexte, ce travail de thèse s'intéresse à l'utilisation d'optiques sub-lambda ou métasurfaces optiques en matériau diélectrique au sein de systèmes d'imagerie infrarouge. De telles optiques sont peu encombrantes et fabriquées par des moyens issus de l'industrie de la microélectronique ce qui permet d'envisager une fabrication collective donc une diminution des coûts. Ces objets sont obtenus en structurant un substrat plan avec des motifs de taille inférieure à la longueur d'onde. La géométrie de ces motifs, dans des matériaux à forts indices de réfraction et transparents dans l'infrarouge comme le silicium, permettent de modifier les propriétés d'une onde optique : sa polarisation, sa phase, sa dispersion et la transmission. Cependant il est complexe de contrôler tout ces paramètres tout en prenant compte des limites technologiques des outils de fabrication. Ce travail s'est donc orienté vers la conception de systèmes optiques mêlant lentilles réfractives et lames sub-lambda de correction de front d'onde. Pour ce faire nous avons (i) développé un outil de simulation mêlant calculs électromagnétiques par la méthode RCWA, pour rendre compte du comportement d'une optique sub-lambda, et conception optique pour la partie réfractive. Nos optiques sub-lambda ont dès lors des dimensions millimétriques à centimétriques pour être couplées à des lentilles réfractives au sein de systèmes d'imagerie, et notre méthode permet de simuler efficacement de tels systèmes optiques. Dans un second temps nous avons (ii) développé des procédés de fabrication de prototypes d'optiques sub-lambda, notamment pour la correction d'aberration sphérique dans le LWIR (bande 8-14µm de longueur d'onde). (iii) Enfin la caractérisation de nos systèmes optiques a permis de valider notre modèle et de démontrer une forte amélioration de la FTM d'un système optique aberrant associé à une lame sub-lambda de correction de front d'onde (FTM multipliée par 3 à 25 cycles par millimètre). Nos derniers résultats montrent une amélioration sur une bande 8-12µm de nos systèmes optiques et ouvrent la voie vers la conception d'optiques sub-lambda large bande au sein de systèmes d'imagerie infrarouge. / In the field of infrared imaging, there are two main types of detectors : cooled detectors, with great sensitivity but expensive, and uncooled detectors, exhibiting precise temperature measurement at moderate cost. In both technologies, the optical systems associated with the detectors represent an important part of the overall cost because of the unitary fabrication process of infrared lenses and the need of more resolved imaging system to follow the shrinkage of the pixel and the increasing array format. Thus, it is important to search for cost effective and low footprint optical solutions exhibiting a high level of performance for infrared imaging systems. In this thesis work we study how dielectric subwavelength structures, or metasurfaces, can adress these issues in infrared systems. Such devices can be made using microelectronics based collective fabrication process, which are cost effective compared to molded infrared optics. Subwavelength optics can be made with silicon, which is transparent in long wave infrared (LWIR) imaging and exhibiting a high refractive index. By designing the geometry of resonators with subwavelength dimensions, one can control light properties like its polarization, phase, transmission and dispersion. However as it is challenging to control all those parameters, even more with fabrication process limitations, we first propose to mix refractive lenses with subwavelength phase blades which correct wavefront errors. (i) We first developed a time effective simulation method mixing electromagnetic calculations with RCWA, for the subwavelength part of the optical system, and classical optical design for the refractive optics. It is worth noting that our subwavelength optics have millimetric to centimetric dimensions to be coupled with refractive lenses, and our method allows us to simulate the overall system. (ii) Then we developed the fabrication process for prototyping subwavelength optics, mainly for spherical aberration correction in LWIR imaging systems. (iii) Finally, we conducted optical characterisations of our systems to validate our model. Our subwavelength optics show an important improvement of the MTF (more than 3 times better at 25 cycles per millimeter) of an optical infrared system by correcting its spherical aberration. Our last results show a improvement of the image quality on a large bandwith (8-12µm) paving the way to large bandwidth subwavelength optics in infrared imaging systems.

The ability to resolve molecules individually has many potential applications. These include understanding the local environments of single molecules including details of their interactions with surroundings. The ability to individually address and manipulate the spin states is also required for spin based quantum information processing. Although optical detection techniques, such as optically detected electron spin resonance (ESR) seem very powerful in these contexts, multiple molecules in the focal volume of a diffraction limited confocal microscope spot cannot in general be resolved individually. Here we propose to solve this problem using optically detected ESR imaging based on the use of high field gradients. In the present research, subwavelength single molecule imaging is demonstrated by using the optically detected ESR technique and the optically detected electron spin echo envelope modulation (ESEEM) technique. Ultra fast Rabi nutation experiments are also performed to demonstrate the feasibility of fast spin manipulations at a low microwave power. Micrometer sized gradient coils, together with micrometer sized co-planar microstrip transmission lines, are designed and fabricated by optical lithography in order to produce the necessary high magnetic field gradients. These fabricated devices are used to demonstrate this subwavelength imaging technique by imaging single electron spins of the nitrogen-vacancy (NV) defect in diamond. In this demonstration, multiple NV defects, unresolved in a single focal volume of a diffraction limited microscope are successfully resolved by the optically detected ESR techniques. Specifically, two neighboring NV defects separated by about 170nm are resolved. Ultra Fast electron spin nutation with an oscillation period of 1.33ns is also achieved by the high microwave magnetic field induced by the current flowing through the fabricated co-planar microstrip lines. These optically detected ESR and ESEEM techniques combined with the micrometer sized gradient coil may find many applications, including single molecule imaging and quantum information processing.

Un défi majeur dans les réseaux d’aujourd’hui est de combler l’écart entre la haute vitesse de la transmission optique et la vitesse plus limitée du traitement électronique des données. Une option est de commuter les données directement dansle domaine optique. Dans cette thèse, nous proposons plusieurs solutions permettant la commutation dans le domaine optique à une granularité plus fine que la longueur d’onde, technique que nous appelons commutation sous-longueurd’onde. Pour montrer la pertinence des solutions proposées, nous analysons leur performance en termes de capacité de trafic, de débit et de délai. La performance est évaluée à la fois par des simulations et en utilisant des modèles de filesd’attente appropriés. Nous considérons d’abord le cas des réseaux métropolitains (Metropolitan Area Networks, MAN) et nous étudions la performance d’un anneau optique avec multiplexage en longueur d’onde (Wavelength Division Multiplexing, WDM) dans lequel la communication entre les noeuds du réseau se fait par insertion/extraction de données dans des créneaux temporels. Nous présentons un protocole entièrement distribué conçu pour assurer l’équité dansce réseau. Nous proposons également un mécanisme d’assemblage de paquets capable d’assurer des délais faibles ainsi que des taux de remplissage élevés. Nous proposons ensuite des solutions de commutation sous-longueur d’onde qui peuvent être appliquées dans le cas plus général des réseaux asynchrones. D’abord, nous proposons de résoudre le problème des collisions de la commutation optique par rafale (Optical Burst Switching, OBS) par la mise en oeuvre d’un mécanisme de réservation. Afin de maximiser l’utilisation des ressources, nous proposons d’adapter la taille de la rafale optique à la charge du réseau.Ensuite, nous proposons une solution alternative pour construire un réseau coeur tout-optique. A cette architecture, nous associons un protocole d’accès ainsi qu’un algorithme d’allocation dynamique de bande passante et nous analysons les performances de la solution proposée. Par le biais d’une étude de cas, nousmontrons que notre solution est capable de réduire considérablement la consommation énergétique par rapport aux architectures actuelles basées sur des routeurs IP. Enfin, nous proposons un nouveau dispositif optique capable derésoudre la contention directement dans le domaine optique. Nous montrons que ce dispositif simple peut être utilisé pour construire des réseaux optiques dynamiques à courte portée tels que les réseaux d’accès ou les centres de traitement de données. / A key challenge in today’s networks is to bridge the gap between high-speed optical transmission and limited electronic processing. This can be achieved by enabling payload to be switched directly in the optical domain.A simple solutionto provide optical switching is by allocating one wavelength channel to each source-destination pair, a technique called Optical Circuit Switching (OCS). Due to lack of sharing, OCS suffers from limited scalability. To overcome this issue,the capacity of each wavelength channel must be dynamically shared among different source-destination pairs. This requires data to be switched at subwavelength granularity by means of subwavelength switching. In this thesis, wepropose several solutions which enable subwavelength switching in optical networks. To show the relevance of the proposed solutions, we analyse their performance in terms of traffic capacity, flow throughput and packet delay. Performance is evaluated both through simulations and by means of appropriate queueing models. We first consider the case of Metropolitan Area Networks (MAN) and we study the performance of synchronous time-slotted Wavelength DivisionMultiplexing (WDM) ring in which network nodes communicate by inserting and extracting data from time-slots. We present a fully distributedMedia Access Control (MAC) protocol designed to ensure fairness. We also propose a burst assembly mechanism able to ensure low assembly delays and high fill rates of the optical time-slots. We then propose subwavelength switching solutions which can be applied in the more general case of asynchronous wide area networks. We first propose to solve the contention problems of conventional Optical Burst Switching (OBS) and the low utilization issue of wavelength-routed OBS byimplementing a two-way reservation OBS scheme in which the size of the opticalburst increases proportionally with the network load so as to maximize resourceutilization. Next, we propose a solution for building an all-optical wide area network based on multipoint-to-multipoint lightpath sharing. We also design an associated MAC protocol and a dynamic bandwidth allocation algorithm and analyse the performance of the proposed solution. By means of a case study, we show that the proposed solution has the potential to considerably reduce power consumption with respect to current router-based architectures. Finally, we propose a novel optical device able to solve contention directly in the optical domain withoutrequiring any optical buffering, electronic signalling or header processing. We show that thissimple device can be used as a building block for dynamic and power efficient short-range optical networks such as access networks or data centers.

Les effets Pockels de deuxième ordre et les effets Kerr de troisième ordre font partie des effets importants exploités pour la modulation de la lumière et la génération de sources dans les plateformes technologiques de la photonique intégrée. Pour tirer parti de ces non-linéarités en photonique au silicium, l'utilisation de structures optiques sub-longueurs d'onde a été explorée. Dans ce contexte, ce travail de thèse s'est concentré sur deux aspects principaux, notamment : 1) L’exploration d'un nouveau schéma de cavité photonique pour tirer profit de l'effet Pockels électro-optique dans les structures de silicium contraint pour la réalisation de modulateurs ultra-rapides à faible consommation ; 2) L’exploration d'une nouvelle famille de guides d'ondes conduisant à une satisfaction automatique des lois de conservation énergie/vecteur d’onde pour la génération de peignes de fréquence Kerr au sein des plateformes photoniques intégrées (notamment silicium).Pour améliorer les performances des modulateurs optiques Si résonants intégrés, nous avons mis au point un nouveau résonateur à cavité de Fano qui, grâce à une ingénierie sub-longueur d'onde (λ=1.55µm), a permis d'obtenir simultanément un taux d'extinction élevé (23 dB) avec un faible facteur Q de seulement 5600, et caractérisé par une très faible consommation électrique inférieure à 5 fj/bit quand on utilise l'effet de modulation par dispersion plasma des porteurs libres. Nous avons étendu la méthode à la conception d'une structure de modulation Fano en silicium contraint dont les performances souffrent traditionnellement de la faible amplitude de l'effet Pockels induit par la déformation exploitée et des pertes micro-ondes considérables dues à des composants de grande surface. Au moyen du résonateur Fano ultra-compact à structuration sub-longueur d'onde, une amélioration d'environ 200 fois/60 fois (facteurs Q de 32000/5600) du rapport d'extinction de modulation avec la même tension de commande a été théoriquement prévue. Pour améliorer l'exploitation des non-linéarités Kerr des structures silicium, nous avons proposé une nouvelle famille de guides d'ondes optiques pour satisfaire automatiquement les lois de conservation de l'énergie et du vecteur d’onde des procédés de mélange à quatre ondes (FWM). La conception de la section des guides d'ondes est basée sur un principe hérité des puits quantiques et des concepts hérités des structures sub-longueur d'onde pour la réalisation des profils d'indice particuliers. En nous basant sur ces guides d'ondes spécifiques en terme de dispersion chromatique, nous les avons appliqués à la modélisation des micro peignes de fréquence (en utilisant des résonateurs à micro anneaux) en résolvant l’équation non linéaire pertinente (Lugiato-Lefever) pour analyser de façon dynamique le processus de génération du spectre des peignes à solitons dans diverses configurations. En complément de ce modèle, les guides d'ondes sub-longueur d'onde à accord de phase automatique ont été considérés pour étendre la largeur de bande des peignes de fréquence à solitons, démontrant une largeur de bande élargie et une meilleure flexibilité dans la réalisation des peignes de fréquence relativement aux démonstrations des travaux précédents. Dans l'ensemble, l'une des caractéristiques dominantes de notre étude a été de contribuer à montrer que les structures photoniques sub-longueur d'onde pouvaient apporter des solutions concrètes aux problèmes utiles à la réalisation de fonctions non linéaires sur puce. Les nano-structures sub-longueur d’onde permettent non seulement une amélioration des circuits photoniques passifs, sujet intensivement développé depuis dix ans, mais ont également un fort potentiel pour la réalisation des fonctions actives. Cette boîte à outils de structures sub-longueur d'onde est décisive dans la pratique pour la réalisation concrète de fonctions optiques nonlinéaires intégrées, en particulier en photonique silicium. / Second-order Pockels and the third-order Kerr effects are among the important effects exploited for light modulation and light generation in integrated photonic platforms. To take advantage of these nonlinearities in silicon photonics, especially due to the lack of second order effect in bulk Si, the use of subwavelength optical structures is explored. In this context, this thesis work has focused on two main aspects, including: 1) Exploration of a novel photonic cavity scheme to take benefit of the electro-optical Pockels effect in strained Si structures for the realization of ultra-fast lower-consumption compact silicon modulators; 2) Exploration of a new family of waveguides leading to an automatic satisfaction of energy/momentum conservation for the purpose of Kerr frequency comb generation in integrated photonic platforms. For improving the performances of integrated silicon resonant optical modulators, we have developed a novel Fano cavity resonator enabled by sub-wavelength engineering, leading simultaneously to high extinction ratio (23 dB) with a small Q factor of only 5600, and characterized by an ultra-low power consumption of less than 5 fj/bit when relying on the free carrier plasma dispersion effect. We have further extended the method to design a strained silicon Fano modulation structure which performances traditionally suffer from the weak amplitude of the exploited strain-induced Pockels effect and from considerable microwave losses due to large footprint components. By means of the proposed ultra-compact subwavelength structured Fano resonator, around 200-fold/60-fold (Q factor of 32000/5600) improvement on the modulation extinction ratio with the same driven voltage was theoretically predicted. For improving the exploitation of silicon Kerr nonlinearities, we have proposed a novel family of graded index optical waveguides intending to automatically fulfill the energy and momentum conservation laws of four-wave mixing processes. The design of the waveguide section is based on a principle inherited from quantum wells of wave mechanics and concepts inherited from subwavelength structures for the practical realization of the rather particular index profiles. Standing on these specific waveguides in term of light dispersion, we have applied them to the modeling of frequency micro-combs (e.g. frequency combs generated using micro-ring resonators and a CW light source) by solving the nonlinear relevant equations (Lugiato-Lefever) to dynamically analyze the soliton comb spectrum generation process in various configurations. On top of this model, the specifically automatically phase-matched sub-wavelength-enabled graded-index waveguides were considered to trim and extend the bandwidth of silicon soliton frequency combs, demonstrating enlarged bandwidth and improved spectrum design flexibility with respect to previous works. Overall, one of the dominant features of our study was to contribute to showing that sub-long wavelength photonic structures could provide concrete solutions to problems useful for the realization of on-chip non-linear functions. Subwavelength/nano structures not only benefit to passive photonic circuits which have been intensively developed in the past ten years, but also show strong potentials in the realization of active functions. This subwavelength toolbox is decisive in practice for the concrete achievement of the objectives pursued.

Les nanostructures ont montré leur utilité dans diverses applications optiques. Notre intérêt s'est porté sur deux d'entre elles : le filtrage spectral et la spectroscopie d'absorption. Dans le premier cas, l'application est notamment limitée par la réjection hors de la bande passante des nanostructures filtrantes.Dans cette thèse, j'ai étudié et développé une structure membranaire composée de deux réseaux métalliques sublongueur d'onde encapsulés dans un diélectrique. Cette structure présente une extinction aux hautes longueurs d'onde qui permet d'améliorer la réjection du filtre. Un procédé de fabrication a été développé, et les caractérisations optiques ont permis de mettre en évidence expérimentalement la présence de l'extinction de la transmission.Dans le second cas, les nanoantennes classiquement utilisées nécessitent une optimisation de la structure pour chaque liaison observée et limitent le type de molécules détectables. J'ai proposé une nouvelle méthode de spectroscopie d'absorption de molécules basée sur des nanogrilles. Ces structures composées d'un réseau de barreaux diélectriques suspendus présentent une réflexion parfaite perturbée par la présence de molécules autour de ces barreaux. J'ai montré théoriquement le potentiel de cette méthode basée sur le balayage spectral de la réflexion résonante grâce à l'angle d'incidence et je l'ai comparée aux nanoantennes métalliques décrites dans la littérature.J'ai ensuite fabriqué et caractérisé des nanogrilles de deux sections différentes et montré l'impact de paramètres expérimentaux sur notre méthode de détection. / Nanostructures have demonstrated their utility in different optical applications. Our interest has focused on two of them: the spectral filtering and absorption spectroscopy. In the first case, the application is limited in particular by the rejection outside the passband of the filter nanostructures.In this thesis, I studied and developed a free-standing structure composed of two metalic subwavelength gratings encapsulated in a dielectric. This structure has an extinction at high wavelengths which improves the filter rejection. A fabricating process has been developed, and optical characterizations demonstrate experimentally the presence of the extinction of the transmission.In the second case, the nanoantennas conventionally used require optimization of the structure for each observed bond and limit the type of detectable molecules. I have proposed a new method of absorption spectroscopy of molecules based on nanorods. These structures composed of a free-standing dielectric rods array exhibit a perfect reflection disturbed by the presence of molecules around these rods. I have theoretically shown the potential of this method based on the spectral scanning reflection resonant with the incident angle and I compared to metalic nanoantennas described in the literature.Then, I fabricated and characterized nanogrilles of two different sections and showed the impact of experimental parameters on our detection method.

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