Le complexe d'accélérateurs du grand collisionneur de hadrons (le Large Hadron Collider - LHC) sera mis à jour lors du long arrêt de la période LS3 en 2023-2025 pour passer à la phase de haute luminosité (HL-LHC). La luminosité instantanée sera multipliée par 5 pour atteindre 7.5×10³⁴ cm⁻²s⁻¹, ce qui correspond à environ 200 collisions inélastiques par croisement de paquets comparé aux 50 par croisement au LHC. Pendant le fonctionnement du HL-LHC, afin d'atteindre une haute précision dans les études des processus physiques du modèle standard et les recherches de nouvelle physique, le collisionneur à protons devra fournir une luminosité intégrée de l’ordre 400 fb⁻¹ par an pendant une dizaine d’années soit 4000 fb⁻¹ escomptées. Ceci représente un ordre de grandeur supérieur à l'ensemble de la période du LHC. Le détecteur interne (Inner Detector) ATLAS actuel ne sera pas en mesure de faire face efficacement à l'augmentation du taux d'événements et de la dose de rayonnement. Afin d’obtenir des performances au minimum égales ou supérieures à celles de la phase LHC, et tenant compte d’un environnement plus hostile en termes de radiations et d’empilements d’évènements, il a été décidé d’opérer le remplacement complet du trajectomètre interne ou Inner Tracker (ITk); à cette fin, une technologie tout silicium a été choisie. Cette thèse est axée sur l'étude de nouveaux capteurs pixels planaires fins à bords très minces, basés sur le concept d’utilisation de matrices de diodes à implants dopés n sur un substrat dopé p. Ce choix est motivé par les critères de meilleure performance intrinsèque, de radio-tolérance élevée ainsi qu’un coût de production optimisé pour de grandes surfaces. Dans ce travail, des capteurs de différentes épaisseurs allant de 50 μm à 150 μm dotés de bords actifs et minces ont fait l’objet d’études approfondies notamment lors de leur fonctionnement à haut flux de particules chargées. De nombreuses analyses minutieuses ont été menées pour déterminer leur résolution en position à l’aide d’un télescope de faisceau de haute énergie. Les régions d’impacts sur la zone active des pixels ainsi que sur la région des contours ont été scrutées avant et après leur irradiation. En effet, de nombreux résultats obtenus en faisceau de protons et électrons seront montrés, notamment une étude comparative des différents concepts de matrices de capteurs de pixels planaires lus avec la puce de lecture « FE-I4 » en technologie CMOS 130 nm. Préparant la phase future du LHC, nous montrerons les premiers résultats obtenus avec la nouvelle génération de pixels granulaires. Ces matrices ont été couplées à la nouvelle puce de lecture frontale récemment développée au CERN, utilisant la technologie CMOS 65 nm. Ces capteurs dotés d’ une plus fine granularité de 50×50 μm² , ont un pas optimisé lequel est nécessaire pour maintenir un taux d'occupation aussi bas que possible dans un contexte de multiplicités de particules chargées très élevées. Dans ce travail, une contribution personnelle à l’électronique de lecture sera détaillée, en particulier les études ont été menées sur la puce nommée «Ring-Oscillator» ou moniteur de radiations, développée au laboratoire. On décrira son comportement dynamique en fonction de la température, de la tension nominale et en conditions hautement radiatives (500 MRad). La mise au point d’un nouvel outil de caractérisation de détecteurs pixels a fait l’objet d’un développement important. Grâce à un ensemble basé sur une excitation laser de 1060 nm, il sera possible de disposer d’un système précis et autonome capable de mesurer rapidement les caractéristiques fonctionnelles des matrices de pixels avec une excellente résolution spatiale. Les caractéristiques de cet outil feront l’objet d’une présentation exhaustive. / The Large Hadron Collider (LHC) will go through the accelerator complex upgrade during the LS3 long shutdown in 2023-2025 to move to the High Luminosity phase (HL-LHC). As a result, an instantaneous luminosity will increase sevenfold to 7.5×10³⁴ cm⁻²s⁻¹, corresponding to approximately 200 inelastic collisions per bunch-crossing, whereas the LHC runs resulted in up to 50 collisions per bunch-crossing. During the operation of the HL-LHC, in order to achieve high-precision in studies of Standard Model processes and searches for new physics, about 4000 fb⁻¹ of integrated luminosity be collected, which is of an order of magnitude larger than over the entire LHC period. The present ATLAS Inner Detector (ID) will not be able to efficiently cope with the increased event rate and radiation dose. Due to this fact the complete replacement of the ID is foreseen with fully silicon Inner Tracker (ITk) to provide high tracking performance in harsher environment delivered by the HL-LHC. This thesis is focused on the study of new n+-in-p planar silicon sensors, as a promising option to instrument the ITk pixel layers, considering their radiation hardness and cost-effectiveness. Sensors of different thicknesses ranging from 50 µm to 150 µm of active and slim edge designs have been tested at a high energy particle beam to investigate hit efficiency performance analyzed on the pixel active area and on the edge area before and after irradiation. The test beam results and their comparison for the different designs of the pixel sensors compatible with FE-I4 readout chip are discussed. Also, the first results on test beam characterization of the pixel modules employing a newly developed prototype of readout chip for the ITk, RD53A chip, implemented in 65 nm CMOS technology, were obtained. The sensors with the decreased to 25×100 µm² and 50×50 µm² pixel pitch to maintain the lower level of occupancy at high particle multiplicity were measured. Additionally, the tests of ring oscillators, contained in RD53A chip, which may be used as a monitor of the received radiation dose, were carried out depending on temperature, supplied voltage and irradiation level up to 500 MRad. Finally, the test bench setup for silicon pixel detectors characterization using an infra-red laser has been the subject of an original development in this thesis. The setup was developed in the clean room at Laboratoire de l'accélérateur linéaire (LAL) and it is capable of rapidly measuring the functional characteristics, providing a flexible charge injection with well-defined hit position to characterize the silicon pixel matrixes. The software to control the setup was created using LabVIEW programming environment. The results of the measurements with the FE-I4 module implemented with openings allowing the laser beam passage on a sensor backside are presented in this thesis.

Les cartes planaires sont des graphes planaires dessinés sur la sphère et vus à déformation près. De nombreuses propriétés des cartes sont supposées universelles, dans le sens où elles ne dépendent pas des détails du modèle choisi. Nous commençons par établir une inégalité isopérimétrique dans la quadrangulation infinie du plan. Nous confirmons également une conjecture de Krikun portant sur la longueur des cycles les plus courts séparant la boule de rayon $r$ de l'infini. Dans un deuxième temps, nous nous intéressons à l'effet de modifications de distances sur la géométrie à grande échelle des quadrangulations uniformes, élargissant la classe d'universalité de la carte brownienne. Nous montrons également que la bijection de Tutte, entre quadrangulations et cartes planaires, est asymptotiquement une isométrie. Enfin, nous établissons une borne supérieure sur le temps de mélange de la marche aléatoire dans les cartes aléatoires. / Planar maps are planar graphs drawn on the sphere and seen up to deformation. Many properties of maps are conjectured to be universal, in the sense that they do not depend on the details of the model.We begin by establishing an isoperimetric inequality in the infinite quadrangulation of the plane. We also confirm a conjecture by Krikun concerning the length of the shortest cycles separating the ball of radius $r$ from infinity. We then consider the effect of modifications of distances on the large-scale geometry of uniform quadrangulations, extending the universality class of the Brownian map. We also show that the Tutte bijection, between quadrangulations and planar maps, is asymptotically an isometry. Finally, we establish an upper bound on the mixing time of the random walk in random maps.

Les matériaux discrets entrecroisés (DIM) rigides sont une classe de matériaux qui se distinguent par la manière unique par laquelle ils se déforment: les DIMs sont composés d’éléments (connectés par entrecroisements) qui peuvent se déplacer librement à l’intérieur d’une amplitude définie par les contacts avec leurs éléments voisins. Ceci donne une réponse biphasique aux déformations unique à ces structures où soit aucune résistance n’est fournie à une déformation, soit un arrêt complet à la déformation se présente. Il n’est pas clair comment l’ensemble de paramètres discrets et continus décrivant un DIM influence ce comportement biphasique. De plus, nous ne possédons pas les outils pour le charactériser correctement. Dans le but d’élucider ce comportement, nous présentons une méthode qui s’inspire de techniques d’homogénisation qui peut détecter les contacts physiques entre éléments composés de tores. En définissant une énergie adéquate, nous pouvons minimiser les intersections entre éléments tout en déformant le DIM d’une façon arbitraire en utilisant des techniques d’optimisation standardes. Nous explorons les déformations auxquelles des arrangements planaires de DIMs peuvent être assujettis et investiguons comment le couplage de contraintes dans deux directions orthogonales influence ces déformations. Nos résultats permettent de mieux comprendre comment différents paramètres décrivant un DIM influence ces déformations. / Rigid discrete interlocking materials (DIMs) are a class of materials that distinguish themselves by the unique way in which they deform: in DIMs, elements (connected through interlocking) can move freely within a range defined through contacts with neighbouring elements. This results in a biphasic deformation behaviour unique to these structures where no resistance is provided to deformation or a hard stop to deformation is met. It is yet unclear how the set of discrete and continuous parameters describing a DIM influences this biphasic behaviour. Likewise, we lack tools to properly characterize it. To that effect, we present a method which takes inspiration from homogenization and handles contacts by leveraging the definition of implicit surfaces, specifically tori, making up our elements. By defining an adequate energy function, we can minimize intersection between elements while deforming the DIM in an arbitrary way using standard optimization approaches. We explore the deformations that planar sheets of DIM can be subjected to and investigate how the coupling of constraints in two orthogonal directions affects these deformations. Our results give insights on how the tuning of various parameters describing the DIM affects these deformations.

Electric vehicles are increasing on the market and new technologies are being investigated because of the demand placed on electrified drivelines to provide maximum efficiency. Electric motors are expected to provide high efficiency and thus precise and compact designs of sensors for electric motors are requested. Market sensors offers a broad variety of sensors which are useful and optimal for different applications. Inductive sensors are investigated by industries because of their characteristics of having high accuracy, robustness, compact and flexible design and tolerant to harsh environments. This thesis is an investigation of inductive position sensors for automotive rotor applications,requested by one of Sweden’s largest companies within the automotive industry. The goal of the project is to design and implement theory of tradtional resolver technology on a printed circuit board (PCB) and conduct concept verifications of the system. Furthermore a new concept in the design is introduced and applied to the angular position sensor, working as a vernier scale and improve the resolution. Results and outcomes of this thesis are meant to facilitate future work and breakthroughs regarding inductive position sensors. This thesis aim to conduct a deep dive in electronics and signal processing and to derive the fundamentals of electromagnetism, from Maxwell’s equations to modern sensor design and to bring a new discussion to the table regarding the traditional measuring target used for rotor position in automotive industries. A new design working as rotor target design is presented and verified in this thesis and the results and outcomes are meant to facilitate future work and breakthroughs regarding inductive position sensors and potentially increase the accuracy and thus the efficiency of electric vehicles.

With increasing frequency up to the THz frequency range and the desire to optimize performance of modern applications, precise knowledge of the dielectric material parameters of a substrate being used in a planar application is crucial: High performance of the desired device or circuit can often be achieved only by properly designing it, using specific values for the material properties. Especially the integration of planar devices for very broadband applications at high frequencies often demands specific dielectric properties such as a low permittivity, dispersion and loss, assuring a predictable performance over a broad frequency range. Therefore, material characterization at these frequencies is of interest to the developing THz community, although not a lot of methods suitable in terms of frequency range and measurement setup exist yet. In this work, a comprehensive method for dielectric material parameter determination from S-Parameter measurements of unloaded and loaded planar transmission lines up to THz frequencies is developed. A measurement setup and methodology based on wafer prober measurements is established, which allows for characterization of planar substrates and bulk material samples alike. In comparison with most existing methods, no specialized measurement cell or cumbersome micro-machining of material samples is necessary. The required theory is developed, including a discussion of effective parameter extraction methods from measurement, identification of and correction for undesired transmission line effects such as higher order modes, internal inductance and surface roughness, as well as mapping and modelling procedures based on physical permittivity models and electromagnetic simulations. Due to the general approach and modular structure of the developed method, new models to cover additional aspects or enhance its performance even further are easily implementable. Measurement results from 100 MHz to 500 GHz for planar substrates and from 100 MHz to 220 GHz for bulk material samples emphasize the general applicability of the developed method. It is inherently broadband, while the upper frequency limit is only subject to the fabrication capabilities of modern planar technology (i.e. minimum planar dimensions of transmission lines and height of substrate) and thus is easily extendable to higher frequencies. Furthermore, the developed method is not bound to a specific measurement setup and applicable with other measurement setups as well, as is exemplary presented for a free-space setup using antennas, enabling measurement of large, flat material samples not fitting on the wafer prober. Several substrate and bulk material samples covering a wide range of permittivities and material classes are characterized and compared with reference values from literature and own comparison measurements. The uncertainties for both planar substrate as well as bulk material sample measurements are estimated with a single-digit percentage. For all measurements, the order of magnitude of the dielectric loss tangent can be determined, while the lower resolution boundary for bulk material sample measurements is estimated to 0.01. Concerning measurements in the wafer prober environment, fixture-related issues are a main cause of measurement uncertainty. This topic is discussed as well as the design of on-wafer probe pads and custom calibration standards required for broadband operation at THz frequencies. / Mit zunehmender Erschließung des THz-Frequenzbereichs und der zugehörigen Optimierung moderner Anwendungen ist eine genaue Kenntnis der dielektrischen Materialparameter verwendeter planarer Substrate unabdingbar: Eine hohe Performance angestrebter Bauteile oder Schaltungen kann nur durch einen präzisen Entwurf sichergestellt werden, wofür spezifische Werte für die Materialeigenschaften bekannt sein müssen. Insbesondere die Integration planarer Bauelemente für sehr breitbandige Anwendungen bei hohen Frequenzen bedingt spezifische dielektrische Materialeigenschaften, wie bspw. geringe Permittivität, Dispersion und Verluste, sodass eine vorhersagbare Performance über einen breiten Frequenzbereich sichergestellt werden kann. Materialcharakterisierung bei diesen Frequenzen ist folglich von Interesse für die sich entwickelnde THz-Forschungslandschaft, wenngleich derzeit kaum Verfahren existieren, die geeignet in Bezug auf den Frequenzbereich oder Messaufbau sind. Im Rahmen dieser Arbeit wird ein umfassendes Verfahren zur Bestimmung der dielektrischen Materialparameter aus S-Parameter-Messungen unbelasteter und belasteter planarer Leitungen bis in den THz-Bereich entwickelt. Ein Messaufbau mitsamt Messmethodik basierend auf Wafer Prober-Messungen wird entworfen, welcher die Charakterisierung von planaren Substraten und losen Materialproben ermöglicht. Im Vergleich zu existierenden Verfahren ist weder eine spezielle Messzelle noch eine umständliche Mikrobearbeitung der Materialproben notwendig. Die Entwicklung der hierfür notwendigen Theorie beinhaltet eine Diskussion von Methoden zur Extraktion effektiver Parameter aus Messungen, die Identifikation und Korrektur unerwünschter Leitungseffekte wie bspw. höherer Moden, interner Induktivität und Oberflächenrauhigkeit sowie Zuordnungs- und Modellierungsverfahren basierend auf physikalischen Permittivitätsmodellen und elektromagnetischen Simulationen. Durch den allgemeinen, modularen Ansatz des entwickelten Verfahrens lassen sich neue Modelle zur Berücksichtigung zusätzlicher Effekte oder weiteren Verbesserung der Performance einfach einarbeiten. Messergebnisse von 100 MHz bis 500 GHz für planare Substrate und von 100 MHz bis 220 GHz für lose Materialproben unterstreichen die allgemeine Anwendbarkeit des entwickelten Verfahrens. Es ist inhärent breitbandig, wobei eine obere Frequenzgrenze nur durch die Fertigungstoleranzen moderner planarer Technologien gegeben ist (minimale Leitungsdimensionen und Substrathöhe), sodass es einfach zu höheren Frequenzen hin erweiterbar ist. Weiterhin ist das entwickelte Verfahren nicht an einen bestimmten Messaufbau gebunden und auch mit weiteren Aufbauten anwendbar, wie beispielhaft an einem Freiraum-Aufbau mit Antennen präsentiert wird. Eine Vielzahl planarer Substrate und loser Materialproben, die ein weites Spektrum an Permittivitäten und Materialklassen abdecken, werden charakterisiert und mit Referenzdaten aus der Literatur sowie eigenen Messungen verglichen. Die Messunsicherheiten der Permittivitätsmessungen werden im einstelligen Prozentbereich abgeschätzt und der dielektrische Verlustwinkel kann in seiner Größenordnung bestimmt werden. Aufbaubezogene Einflüsse als eine Hauptursache für Messunsicherheiten am Wafer Prober werden adressiert, ebenso wie der Entwurf von On-Wafer Probe Pads und selbsterstellter Kalibrierstandards, die notwendig sind für den Einsatz bei THz-Frequenzen.

When a nanostructure is coupled between two leads, the electron transmission probability as a function of energy, E, is used in the Landauer formula to obtain the electrical conductance of the nanodevice. The electron transmission probability as a function of energy, T (E), is calculated from the appropriate solution of the time independent Schrödinger equation. Recently, a large class of nanostructures called quantum dragons has been discovered. Quantum dragons are nanodevices with correlated disorder but still can have electron transmission probability unity for all energies when connected to appropriate (idealized) leads. Hence for a single channel setup, the electrical conductivity is quantized. Thus quantum dragons have the minimum electrical conductance allowed by quantum mechanics. These quantum dragons have potential applications in nanoelectronics. It is shown that for dimerized leads coupled to a simple two-slice (l = 2, m = 1) device, the matrix method gives the same expression for the electron transmission probability as renormalization group methods and as the well known Green's function method. If a nanodevice has m atoms per slice, with l slices to calculate the electron transmission probability as a function of energy via the matrix method requires the solution of the inverse of a (2 + ml) (2 + ml) matrix. This matrix to invert is of large dimensions for large m and l. Taking the inverse of such a matrix could be done numerically, but getting an exact solution may not be possible. By using the mapping technique, this reduces this large matrix to invert into a simple (l + 2) (l + 2) matrix to invert, which is easier to handle but has the same solution. By using the map-and-tune approach, quantum dragon solutions are shown to exist for single-layer planar rectangular crystals with different boundary conditions. Each chapter provides two different ways on how to find quantum dragons. This work has experimental relevance, since this could pave the way for planar rectangular nanodevices with zero electrical resistance to be found. In the presence of randomness of the single-band tight-binding parameters in the nanodevice, an interesting quantum mechanical phenomenon called Fano resonance of the electron transmission probability is shown to be observed.

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This work discusses the dynamic predictions of compliant mechanisms using the Pseudo-Rigid-Body model (PRBM). In order to improve the number of mechanisms that can be modeled, this research develops and identifies several key concepts in the behavior of beam segments where both ends are fixed to a rigid body (fixed-fixed flexible segments). A model is presented, and several examples are discussed. The dynamic behavior of several compliant segments is predicted using the PRBM and the results are compared to finite element analysis and experimental results. Details are presented as to the transient behavior of a typical uniform rectangular cross section beam. The results of this study are extended and applied to compliant planar mechanisms. It is shown by comparison with finite element analysis and experimental results that the PRBM is a good model of the physical system's dynamic behavior. The method is also demonstrated for use with compliant microelectromechanical (MEMS) systems.

Designing mechanical products in a competitive environment can present unique challenges, and designers constantly search for innovative ways to increase efficiency. One way to save space and reduce cost is to use ortho-planar compliant mechanisms which can be made from sheets of material, or lamina emergent mechanisms (LEMs). This thesis presents principles which can be used for designing LEMs. Pop-up paper mechanisms use topologies similar to LEMs, so it is advantageous to study their kinematics. This thesis outlines the use of planar and spherical kinematics to model commonly used pop-up paper mechanisms. A survey of common joint types is given, as well as an overview of common monolithic and layered mechanisms. In addition, it is shown that more complex mechanisms may be created by combining simple mechanisms in various ways. The principles presented are applied to the creation of new pop-up joints and mechanisms, which also may be used for lamina emergent mechanisms. Models of the paper mechanisms presented in Chapter 2 of the thesis are found in the appendix, and the reader is encouraged to print, cut out and assemble them. One challenge associated with spherical and spatial LEM design is creating joints with the desired motion characteristics, especially where complex spatial mechanism topologies are required. Hence, in addition to a study of paper mechanisms, some important considerations for designing joints for LEMs are presented. A technique commonly used in robotics, using serial chains of revolute and prismatic joints to approximate the motion of complex joints, is presented for use in LEMs. Important considerations such as linkage configuration and mechanism prototyping are also discussed. Another challenge in designing LEMs is creating multi-stable mechanisms with the ability to have coplanar links. A method is presented for offsetting the joint axes of a spatial compliant mechanism to introduce multi-stability. A new bistable spatial compliant linkage that uses that technique is introduced. In the interest of facilitating LEM design, the final chapter of this thesis presents a preliminary design method. While similar to traditional methods, this method includes considerations for translating the mechanism topology into a suitable configuration for use with planar layers of material.

The AER has a vital role in directing embryonic limb development. Several models have been developed that attempt to explain how the AER directs limb development, but none of them are fully supported by existing data. I provide evidence that FGFs secreted from the AER induce a gradient of Wnt5a. I also demonstrate that limb mesenchyme grows toward increasing concentrations of Wnt5a. We hypothesize that the changing shape of the AER is critical for patterning the limb along the proximal to distal axis. To better understand the pathway through which Wnt5a elicits its effects, we have performed various genetic studies. We demonstrate that Wnt5a does not signal via the Wnt/β-catenin pathway. However, we show that Wnt5a mutants share many common defects with Vangl2 mutants suggesting that Wnt5a signals through the Wnt/planar cell polarity (PCP) pathway.