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In this thesis, we used the E-Beam lithography to fabricate a device of coupled microdisk-ring laser on the sample which was grown by molecular beam epitaxy (MBE), and analyzed the coupled effect of the device. The active layer was composed of six compressively strained InGaAs quantum dots (QDs) that were designed to support gain at 1200nm. Under the active layer, we replaced sacrificial layer by distributed bragg reflector (DBR). The purpose of the DBR was used like a mirror to reflect the particular wavelength which located at DBR¡¦s stop band, so the energy would be confined in the active layer. The device was composed of a microdisk and a ring. The diameter of the microdisk was 3£gm, and the width of the ring is 250nm. The microdisk was placed in the ring, and the gap of both was 100nm. After design, we simulated whether the device could generate coupled modes by Finite-Difference Time-Domain (FDTD). In experiment, we used the E-Beam lithography to define negative pattern on the sample which is spread with the PMMA. We also used the thermal evaporation to evaporate the metal, and lift the metal to form our pattern. Finally, we used the dry etching to transform the pattern to the epitaxial layer, and then the device was completed. In measurement, we used the micro-PL to measure our device, and got a successful result. The result showed our device generated eight resonant modes. The measured result matched the simulation result. Through simulation, the device generated three coupled modes, 1173.8nm, 1206nm, and 1214nm. We expect that the device will be used to generate terahertz source in the future.

La détection précoce de biomarqueurs de maladies telles que le cancer représente un intérêt majeur dans le processus de traitement. En effet, un diagnostic avancé augmente considérablement les chances de réussite du traitement. En pratique, cela nécessite des outils permettant de détecter rapidement d'infimes quantités de composants biologiques (anticorps, protéines, ADN...) au sein d'échantillons réels tels que du sang ou du sérum.Ces dernières années, les avancées et progrès technologiques en matière de micro et nanofabrication ont permis le développement des Micro et Nano Systèmes Electro-Mécaniques (M/NEMS) dans de nombreux domaines d'application et notamment celui de la détection de masse. Ainsi, des nano-capteurs de masse atteignant des résolutions de l'ordre du yoctogram ($10^{-24}g$), soit la masse d'un seul proton ont été développés. De telles résolutions permettraient d'utiliser ces capteurs à des fins de biodétection. Ces résultats ont cependant été obtenus sous vide ce qui est incompatible avec le monde biologique. Immergés en liquide, les performances des M/NEMS traditionnels sont drastiquement réduites notamment à cause de l'amortissement du au fluide. Un nouveau type de résonateur à base de microdisques optomécaniques résonants a ainsi vu le jour démontrant un fort potentiel pour la détection en milieu liquide. Là où les méthodes classiques de transduction électriques des M/NEMS éprouvent des difficultés en liquide, l'exceptionnelle sensibilité de la transduction optomécanique permet de surmonter ce problème.Dans ce cadre, ces travaux de thèse visent à développer un biocapteur à base de microdisques optomécaniques résonants en silicium pour la détection biologique en milieu liquide. Le design, la fabrication ainsi que la caractérisation complète de ces capteurs est décrite. Enfin, une preuve de concept de détection de virus T5 à une concentration de quelques pM à l'aide de ces microdisques est également présentée. / Early detection of disease's biomarkers such as cancer represents a major interest in the treatment process. Indeed, a diagnosis at an early stage considerably increases the chance of the treatment to be successful. Practically, tools allowing the rapid detection of tiny amount of biological compounds (antibodies, proteins, DNA...) in real samples such as blood or serum are needed.Over the last years, the advances and progresses of micro and nanofabrication techniques have allowed the development of Micro-Nano Electro Mechanical Systems (M/NEMS) in various fields of application including mass sensing. Thus, nano mass sensors reaching resolution down to the yoctogram level, the equivalent of a single proton have been demonstrated. Such resolution limit would theoretically allow these sensors to be used as potential biosensors. These results were nonetheless obtained in vacuum conditions which is incompatible with the biological world. Immersed in fluid, the performance of traditional M/NEMS are drastically degraded mostly due to the large viscous damping. A new type of object in the form of optomechanical microdisk resonators have recently emerged, demonstrating a huge potential for sensing in liquid. While M/NEMS classical electrical or optical transduction methods become very challenging in liquid, the astonishing sensitivity of the optomechanical transduction overcomes this major issue.In this context, this thesis work aims at developing a biosensor based on silicon optomechanical microdisk resonators for biosensing in liquid. Design, fabrication along with the complete characterization of theses devices is described. Eventually, a proof-of-concept of T5 virus detection at the pM level using these microdisks is presented.

Cette thèse porte sur l'interaction lumière-matière au sein de nanostructures placées dans des cavités optiques à base de semi-conducteurs nitrures. A l'aide d'expériences de micro-photoluminescence dans l'ultra-violet, nous étudions les propriétés optiques de boîtes quantiques GaN/AlN dans des microcavités planaires et celles de puits quantiques GaN/AlN insérés dans des microdisques AlN.Afin d'améliorer la collection du faible signal de photoluminescence de boîtes quantiques uniques, nous utilisons des microcavités planaires pour modifier le diagramme d'émission d'une boîte quantique. Le dessin des microcavités est optimisé grâce à des simulations numériques basées sur la méthode des matrices de transfert en présence d'un émetteur. Nous montrons que, pour une microcavité nitrure à base de miroirs de Bragg AlN/AlGaN, la collection des photons émis par une boîte quantique peut être théoriquement améliorée d'un ordre de grandeur, ce qui est confirmé par nos mesures sur boîtes quantiques uniques, ouvrant ainsi la voie à des études avancées de corrélations de photons dans l'UV.La seconde partie des travaux est dédiée à la réalisation d'un micro-laser opérant dans l'UV profond et à température ambiante. En utilisant des puits quantiques GaN/AlN de 2,8 mono-couches, crûs sur substrat silicium et insérés dans des microdisques AlN, nous observons une émission laser à 275 nm sous pompage optique impulsionnel. Cette démonstration montre le fort potentiel des semi-conducteurs nitrures pour la nano-photonique UV sur silicium. / This thesis addresses the light-matter interaction in nitride nanostructures embedded in optical microcavities. By using micro-photoluminescence experiments, we study the optical properties of GaN/AlN quantum dots embedded in planar microcavities and those of GaN/AlN quantum wells in AlN microdisks.By placing quantum dots in planar microcavities, we are able to modify the emission diagram and increase the collection efficiency. The design of the microcavities is optimized by using numerical simulations based on transfer matrix method with an internal emitter. For an AlN microcavity with AlN/AlGaN Bragg mirrors, we show that the collection efficiency could be theoretical increase by one order of magnitude, which is confirmed by our micro-photoluminescence experiments on single quantum dots. This observation opens the way for advanced studies such as photon correlations experiments in the UV range.The second part of our work is devoted to the realization of a micro-laser operating in the deep-UV range at room-temperature. By using thin GaN/AlN quantum wells (2.8 monolayers), grown on silicon substrate and embedded in AlN microdisks, we observe a laser emission at 275 nm under pulsed optical pumping. This demonstration shows the strong potentiality for future developments of nitride-on-silicon nano-photonics.

Cavity quantum electrodynamics provide a platform to form a quantum network which connects individual quantum bits (qubits) via photon. Optical cavity, a device which traps photons in a confined volume can enhance the interaction between photons and the qubits serves as fundamental building block for a quantum network. Nitrogen vacancy (NV) centers in diamond has emerged as one of the leading solid-state qubits because of its long spin coherence time and single photon emission properties at room temperature. Diamond optical micro-cavities are highly sought after for coupling with NV centers. Fabrication of optical cavities from nano-crystalline diamond film has been demonstrated previously. The quality factor (Q) of such devices was limited by the material properties of the nano-crystalline diamond film. Fabrication of single-crystal diamond photonic cavities is challenging because there is no trivial way to form thin diamond film with optical isolation. In this thesis, we describe an approach to fabricate high quality single-crystal diamond optical cavities for coupling to NV centers in diamond. ingle-crystal diamond membranes were generated using an ion-slicing method. Whispering gallery modes were observed for the first time from microdisk cavities made from such material. However, the cavity Q (∼ 500) was limited by the ion damage created during processing. By using an homo-epitaxial overgrowth method, a high quality diamond film can be grown on the ion damaged membranes. Microdisk cavities with Q ∼ 3,000 were fabricated on these improved materials. Diamond membranes with a delta-doped layer of NV can be made using a slow overgrowth process which demonstrate the position and density of NV centers can be controlled in these membranes. Photonic crystal cavities with Q ∼ 4,000 were fabricated from the delta-doped membranes with cavity resonance near the zero phonon line of NV centers. Different color centers can also be introduced during the overgrowth process, and optical coupling of an ensemble of silicon vacancy centers is demonstrated by coupling to a diamond microdisk cavity. We believe the techniques developed in this thesis could contribute to building of a quantum photonic network using diamond as a platform. / Engineering and Applied Sciences

Optical traveling-wave resonator architectures have shown promise for the realization of many compact photonic functionalities in different research disciplines. Realizing these resonator structures in high-index contrast silicon enables dense and large scale integration of large arrays of functionalized resonators in a CMOS-compatible technology platform. Based on these motivations, the main focus of this Ph.D. research has been on the device physics, modeling, implementations, and applications of planar ultra-high Q silicon traveling-wave microresonators in a silicon-on-insulator (SOI) platform. Microdisk, microring, and racetrack resonators are the three general traveling-wave resonator architectures of interests that I have investigated in this thesis, with greater emphasis on microdisks. I have developed efficient tools for the accurate modeling of these resonators. The coupling to these resonators has been through a nano-waveguide side coupled to them. For this purpose, I have developed a systematic method for engineering a waveguide-resonator structure for optimum coupling. I have addressed the development of nanofabrication techniques for these resonators with efficient interaction with a nano-waveguide and fully compatible with active electronic integration. The outcome of the theoretical design, fabrication, and characterization of these resonators is a world-record ultra-high Q (3×10[superscript 6]) with optimum waveguide-resonator interaction. I have investigated the scaling of these resonators toward the ultimate miniaturization and its impact on different physical properties of the resonators. As a result of these investigations, I have demonstrated miniaturized Si microdisk resonators with radii of ~ 1.5 micron and Q > 10⁵ with single-mode operation over the entire large free-spectral range. This is the highest Q (~ one order more than that in previously reported data) that has been obtained for a Si microdisk resonator with this size on a SiO₂ substrate. I have employed these resonators for more advanced functionalities such as large-scale integration of resonators for spectroscopic and filtering applications, as well as the design of flat-band coupled-resonator filter structures. By proposing a systematic method of design, I have shown ultra-compact coupled-resonator filters with bandwidths ranging from 0.4 to 1 nm. I have theoretically and experimentally investigated the performance of ultra-high Q resonators at high powers and in the presence of nonlinearities. At high powers, the presence of two-photon absorption, free-carrier generation, and thermo-optic properties of silicon results in a rich dynamic in the response of the resonator. In both theory and experiment, I have predicted and demonstrated self-sustained GHz oscillation on the amplitude of an ultra-high Q resonator pumped with a continuous-wave laser.

Orientador: Newton Cesário Frateschi / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-17T02:03:42Z (GMT). No. of bitstreams: 1 Mialichi_JoseRoberto_D.pdf: 4426656 bytes, checksum: f54944bc3408b22608afdd373e3445dd (MD5) Previous issue date: 2010 / Resumo: Esta tese de doutorado apresenta resultados experimentais do crescimento de pontos quânticos de InAs diretamente sobre InGaAsP de baixa energia de bandgap (?g=1420 nm), cujo desenvolvimento visa a obtenção de um meio ativo com emissão na banda C (1520¿1570 nm) para a fabricação de ressonadores de microdisco. Baseado em resultados de fotoluminescência e microscopia de força atômica, o fenômeno da inter-difusão de elementos na interface InAs/InGaAsP é proposto e calculado, indicando a presença de Gálio e Fósforo na composição dos pontos quânticos. O ganho óptico de pontos quânticos de InAs crescidos sobre InGaAsP é também calculado com base nos resultados obtidos na análise de inter-difusão. Subseqüentemente, a teoria dos modos ressonantes no microdisco, particularmente os modos chamados whispering gallery modes (WGMs), é desenvolvida com o intuito de auxiliar os cálculos de fator de qualidade, fator de confinamento e corrente de limiar. Uma estrutura multicamada (diodo PIN) com região ativa baseada em pontos quânticos do sistema InAs/InGaAsP foi crescida por epitaxia de feixe químico (CBE) para a fabricação de ressonadores de microdisco. A fabricação dos microdiscos é feita por litografia óptica, corrosão por plasma de íons e ataque químico seletivo de InP. Feixe de íons focalizados (FIB) foi usado para substituir o ataque por plasma para diminuir a rugosidade das paredes dos discos. Os ressonadores de microdiscos são caracterizados elétrica e opticamente e os resultados são confrontados com base nos resultados teóricos apresentados ao longo da tese. Com base nos resultados das caracterizações eletro/ópticas dos ressonadores, correções como a inclusão de perdas ópticas da rugosidade da borda e aquecimento local foram acrescidas ao modelo teórico, resultando em boa concordância com os resultados experimentais. Por fim, apresentamos o desenvolvimento de dispositivos híbridos a partir de polímeros orgânicos depositados diretamente sobre microdiscos de InGaAs com o objetivo de integrar meio ativo orgânico com ressonadores inorgânicos para aplicações em optoeletrônica. Estes resultados foram obtidos durante o programa de doutorado com estágio no exterior no Laboratório Nacional de Nanotecnologia (NNL) vinculado à Università del Salento (Lecce/Itália) / Abstract:This doctorate¿s thesis presents the growth of InAs quantum dots directly on high bandgap InGaAsP (?g=1420 nm) barriers to be used as the active region of microdisk resonators with emission in the C-band (1520¿1570 nm). Based on photoluminescence and atomic force microscopy experiments, the occurrence of inter-diffusion on the InAs/InGaAsP interface is calculated, suggesting the presence of Gallium and Phosphorus in the quantum dots (QDs) composition. Based also on the inter-diffusion results, the optical gain of the InAs QDs is calculated. Subsequently, microdisk resonator whispering gallery modes (WGMs) are calculated and employed to predicting the cavity quality and confinement factors, as well as the threshold current. A PIN diode with an active region based on InAs QDs was grown by Chemical Beam Epitaxy (CBE) for the fabrication of current injected microdisk resonators. Microdisk fabrication process is performed using photolithography, reactive ion etching and InP selective wet-etching. Focused ion beam is used to replace the plasma etching in order to reduce the roughness of the disk¿s edge. Microdisks resonators are characterized electrically and optically and the measurements are analyzed based on the theoretical results presented along this thesis. Based on these measurements, optical losses caused by disk¿s edge roughness and local heating are added to our simulation tool, resulting in better agreement with the experimental results. Finally, we present the development of hybrid resonators using organic polymer deposited directly on inorganic microdisks integrating an organic active medium with inorganic resonators for optoelectronic applications. These results were obtained during our work at the National Nanotechnology Laboratory (NNL) and the University of Salento (Lecce/Italy) / Doutorado / Física da Matéria Condensada / Doutor em Física

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