With the advancement in knowledge of inelastic response of structures, the design and construction practices of reinforced concrete buildings have been changing worldwide. Most of the codes are incorporating the near-fault factors and performance based designs in the seismic codes. However, further investigation is needed to identify the physical behaviour of multi-storey buildings to near-fault ground motions. At present, quantitative evaluation of response and its mitigation to near field ground motions is a popular topic in earthquake engineering field. The present study discusses the inelastic response of symmetric and asymmetric multi-storey buildings to near-fault ground motions. The possibility of design approach is based on ‘expendable top storey’ for the multi-storey RC- buildings to near field records. If such behaviour is feasible one can conceive of a structure whose top storey is permitted and designed to undergo large inelastic deformations while reducing damage in the lower storey. The concept was first proposed in an earlier research (RaghuPrasad, 1977). Such a concept juxtaposes the often-mentioned ‘soft first storey’ concept. Further in this report, the performance evaluation of multi-storey buildings near Chiplun fault in Mumbai, India is also discussed. The thesis is organized in the following chapters: Introduction in Chapter-1 contains detailed literature review on inelastic response of symmetric and asymmetric buildings, response of buildings to near-fault records, elastic and inelastic vibration absorber concepts and performance based designs. The literature reveals that considerable amount of research has been carried out on the elastic, inelastic response of structures and vibration absorber concepts to ordinary ground motions. Recently, the effect of near field ground motions on the response of multi-storey buildings is gaining much importance. Most of the research publications are available on response of symmetric buildings subjected to near field ground motions. But many problems are yet to be investigated. They are, identification of important ground motion parameters in near fault records, vibration absorber concepts and torsional response of structures subjected to pulse type ground motions. These problems are clearly mentioned in the recently published state-of-the-art review by Shuang and Li-Li (2007). In this report an attempt has been made to solve these problems. Effect of near-fault ground motions on symmetric multi-storey buildings in Chapter-2, describes simplified non-dimensionalized equations of motion to study the response behaviour of multi-storey buildings to near fault records. The non-dimensionalized equations of motion are expressed in terms of near fault ground motion parameters. The objective is to find a relation between ductility demand and near field ground motion parameters through neural network approach. For this a neural network modeling was done to predict the ductility demand in terms of peak ground acceleration, peak ground velocity, epicentral distance and pulse period of the near field ground motion. A thorough sensitive analysis is carried out, to ascertain which parameters are having maximum influence on ductility demand. In this chapter further, a comparative study is made on the inelastic seismic response of multi-storey buildings to pulse type and non pulse type ground motions. The study shows that, it is necessary to consider the effect of near fault ground motions separately and make provisions for the design in the codes of practice accordingly. Vibration absorber effect in multi-storey buildings in chapter-3, discusses the behaviour of top storey as a vibration absorber during near field ground motions. For this purpose, a five storey symmetric building model is considered as an example problem to demonstrate the effectiveness of the proposed concept. Response of the structure is obtained for the various combinations of absorber storey parameters such as mass ratio, frequency ratio and yield displacement ratio. Here mass ratio means mass of the absorber storey to that of the bottom storey and similarly for the frequency and yield displacement ratios. Observing the storey-wise variation of these responses, we can say that for a range of mass ratios, frequency ratios and yield displacement ratios, the inelastic response of top storey is large compared to the lower storeys. This range is termed as ‘effective range’. Further, in this range the top storey absorbs the vibration energy of the structure by keeping the lower storeys in elastic state i.e. acts as a vibration absorber. The top storey can also be termed as ‘expendable top storey’. Effect of near-fault ground motions on asymmetric multi-storey buildings in Chapter-4, discusses the inelastic response of asymmetric buildings to single horizontal component and two horizontal components of near fault ground motions viz., fault normal and fault parallel components. For numerical investigations eight building models are considered. Eccentricity has been created by keeping the stiffness and mass centre separately. The building models are subjected to strong motion records of Imperial Valley Array-5 (1979) and Northridge-Sylmar (1994). A detailed study on the effect of base shear strength, eccentricity and pulse period of near fault ground motions on the response is investigated. Performance of multi-Storey buildings in Chapter-5, reported a detailed procedure for the performance evaluation of structures. The procedure is applied to find the performance evaluation of multi-storeyed buildings located in near fault region. Chiplun fault in Mumbai, India has been chosen for the study because several features of that fault are clearly published (RaghuKanth and Iyengar, 2006). Results of performance evaluation of five and ten storeyed symmetric buildings with and without infill panels are studied. Ground motion records consistent with the hazard spectrum for the design are considered. The performance of the building near the Chiplun fault in Mumbai, India shows operational under UHS-500 (uniform hazard spectrum) event and it collapses when the building is exposed to UHS-2500 record. The thesis is concluded in Chapter-6 with an overall summary of the report and suggestions for further scope of the work.

Surface polaritons, i.e., collective oscillations of the surface charges, strongly influence the optical response at the micro- and nanoscale and have to be accounted for in modern nanotechnology. Within this thesis, certain basic phenomena involving surface polaritons are investigated by means of the semianalytical multiple-multipole (MMP) method. The results are compared to experiments. In the first part, the surface plasmon resonance (SPR) of metal nanoparticles is analyzed. This resonant collective oscillation of the free electrons in a metallic nanoparticle leads to an enhancement and confinement of the local electric field at optical frequencies. The local electric field can be further increased by tailoring the shape of the particle or by using near-field-interacting dimers or trimers of gold nanospheres. The hot spots found under such conditions increase the sensitivity of surface-enhanced Raman scattering by several orders of magnitude and simultaneously reduce the probed volume, thereby providing single-molecule sensitivity. The sub-wavelength-confined strong electromagnetic field associated with a SPR provides the basis for scattering-type near-field optical microscopy or tip-enhanced Raman spectroscopy, where the metal particle serves as a probe that is scanned laterally in the vicinity of a substrate. The presence of the latter causes a characteristic shift of the SPR towards lower frequencies. This effect originates in the near-field interaction of the surface charges on the objects. Furthermore, the excitation of higher-order modes becomes possible in case of an excitation by a strongly inhomogeneous wave, such as an evanescent wave. These modes may significantly contribute to the near field but have only very little influence on the far-field signature. Instead of using resonant probes, one may place a nonresonant probe in the vicinity of a substrate having a high density of electromagnetic surface states. This also produces a resonance of the light scattering by the system. Especially polar crystals, such as the investigated silicon carbide, feature such a high density of surface phonon polariton states in the mid-infrared spectral region, which can be excited due to the near-field interaction with a polarized particle. Thereby, a resonance is created leading to a strong increase of the electric field at the interface. In the second part of the thesis, special emphasis is put on surface plasmon polaritons (SPPs). Such propagating surface waves can be excited directly by plane waves only at patterned interfaces. This process is studied for the case of a groove. The groove breaks the translational invariance, so that the SPPs can be launched locally at the edges of the groove. Additionally, the mode(s) inside the groove are excited. These modes can basically be understood as metal-insulator-metal cavity modes. Their dispersion strongly depends on the groove width. The cavity behavior caused by the finite depth provides another degree of freedom for optimizing the SPP excitation by plane waves. Thin metallic films deposited on glass offer two different SPP waveguide modes, each of which can be addressed preferentially by a proper choice of the width of the groove. The reflection, transmission, scattering, and the conversion of the modes at discontinuities such as edges, steps, barriers, and grooves can be controlled by appropriately designing the geometry at the nanoscale. Furthermore, the excitation of SPPs at single and multiple slits in thin-film metal waveguides on glass and their propagation and scattering is shown by scanning near-field optical experiments. Such waveguide structures offer a means for transporting light in a confined way. Especially triangularly shaped waveguides can be used to guide light in sub-wavelength spaces. / Die Wechselwirkung von elektromagnetischer Strahlung mit subwellenlängenkleinen Teilchen bzw. Oberflächenstrukturen ermöglicht nicht nur eine Miniaturisierung optischer Geräte, sondern erlaubt sehr interessante Anwendungen, beispielsweise in der Sensorik und Nahfeldoptik. In der vorliegenden Arbeit werden die zu Grunde liegenden Effekte im Rahmen der klassischen Elektrodynamik mit Hilfe der semianalytischen Methode der multiplen Multipole (MMP) analysiert, und die Ergebnisse werden mit Experimenten verglichen. Im ersten Teil werden Oberflächenplasmonenresonanzen (engl. surface plasmon resonance - SPR) einzelner und wechselwirkender Metallteilchen untersucht. Die dabei auftretende resonante kollektive Schwingung der freien Elektronen des Partikels bewirkt eine deutliche Erhöhung und Lokalisierung des elektromagnetischen Feldes in seiner Umgebung. Die spektrale Position und die Stärke der SPR eines Nanoteilchens, die von dessen geometrischer Form, Permittivität und Umgebung abhängen, können nur im Grenzfall sehr kleiner Teilchen elektrostatisch beschrieben werden, wohingegen der verwendete semianalytische MMP-Ansatz weitaus flexibler ist und insbesondere auch auf größere Partikel, Teilchen mit komplizierterer Form bzw. Ensembles von Partikeln anwendbar ist. Die betrachteten einzelnen kleinen (< Wellenlänge) Goldkügelchen und Silberellipsoide besitzen eine stark ausgeprägte SPR im sichtbaren optischen Bereich. Diese ist auf eine dipolartige Polarisierung des Teilchens zurückzuführen. Höhere Moden der Polarisation können entweder als Folge von Retardierungseffekten an größeren (mit der Wellenlänge vergleichbaren) Teilchen oder bei der Verwendung inhomogener (z.B. evaneszenter) Wellen angeregt werden. Partikel, die sich in der Nähe eines Substrates befinden, unterliegen der Nahfeldwechselwirkung zwischen den (lichtinduzierten) Oberflächenladungen auf der Oberfläche des Teilchens und des Substrats. Dies führt zu einer Verschiebung der SPR zu niedrigeren Frequenzen und einer Erhöhung des lokalen elektrischen Feldes. Letzteres bildet die Grundlage z.B. der spitzenverstärkten Raman-Spektroskopie und der optischen Nahfeldmikroskopie mit Streulichtdetektion. Dasselbe Prinzip bewirkt ein stark überhöhtes elektrisches Feld zwischen miteinander wechselwirkenden Nanopartikeln, welches z.B. die Sensitivität der oberflächenverstärkten Raman-Mikroskopie um mehrere Größenordnungen steigern kann. Im Gegensatz zur SPR einzelner Nanopartikel kann die Resonanz der Lichtstreuung im Fall eines Partikels in der Nähe eines Substrats aus der durch die Nahfeldwechselwirkung induzierten Anregung elektromagnetischer Oberflächenzustände entstehen. Diese wirken ihrerseits auf das Nanopartikel zurück, wobei eine resonante Lichtstreuung beobachtbar ist. Dieser, am Beispiel einer metallischen Nahfeldsonde über einem Siliziumcarbid-Substrat analysierte, Effekt ermöglicht bei einer ganzen Klasse von polaren Kristallen interessante Anwendungen in der Mikroskopie und Sensorik basierend auf der hohen Dichte von Oberflächenphononpolaritonen dieser Kristalle im mittleren infraroten Spektralbereich und deren nahfeldinduzierten Anregung. Im zweiten Teil der Arbeit werden kollektive Anregungen von Elektronen an Metalloberflächen untersucht. Die dabei auftretenden plasmonischen Oberflächenwellen (engl. surface plasmon polaritons - SPPs) weisen einen exponentiellen Abfall der Intensität senkrecht zur Grenzfläche auf. Diese starke Lokalisierung der Energie an der Oberfläche bildet die Grundlage vieler Anwendungen, z.B. im Bereich der hochempfindlichen Detektion (bio)chemischer Verbindungen oder für eine zweidimensionale Optik (engl. plasmonics). Das Aufheben der Translationsinvarianz längs der Oberfläche ermöglicht die direkte Anregung von SPPs durch ebene Wellen. Die Abhängigkeit dieser Kopplung von der Geometrie wird am Beispiel eines Nanograbens untersucht. Dabei werden neben den SPPs ebenfalls eine oder mehrere Moden im Graben angeregt. Folglich ermöglicht die geeignete Wahl der Grabengeometrie die Optimierung der Umwandlung von ebenen Wellen in SPPs. Im - in der Praxis weit verbreiteten - Fall asymmetrisch eingebetteter metallischer Dünnschichtwellenleiter existieren zwei Moden. In Abhängigkeit von der Grabenbreite kann die eine oder die andere Mode bevorzugt angeregt werden. Die Analyse der Wechselwirkung von SPPs mit Oberflächenstrukturen, z.B. Kanten, Stufen, Barrieren und Gräben, zeigt die Möglichkeit der Steuerung der Reflexions-, Transmissions- und Abstrahleigenschaften durch die gezielte Wahl der Geometrie der "Oberflächendefekte" auf der Nanoskala und deckt die zu Grunde liegenden Mechanismen und die daraus resultierenden Anforderungen bei der Herstellung neuer plasmonischer Komponenten auf. Exemplarisch wird das Prinzip der SPP-Anregung an einzelnen und mehreren Gräben in dünnen metallischen Filmen sowie der subwellenlängen Feldlokalisierung an sich verjüngenden metallischen Dünnschichtwellenleitern unter Verwendung der optischen Nahfeldmikroskopie experimentell gezeigt.

Genom att studera olika kommunikationsprotokoll kunna svara på vad det är som gör att ett visst protokoll är bäst anpassat för att användas mellan mobila enheter och IoT-enheter. I arbetet användes en kvalitativ litteraturstudie för att ge en grundlig teoretisk bakgrund samt en experimentell studie där ett par teorier undersökts ifall de stämmer med resultaten ifrån verkligheten. De fem faktorerna kompatibilitet, batteritid, frekvens, räckvidd och tillförlitlighet undersöktes hos kommunikationsprotokollen Bluetooth Low Energy (BLE), Närfältskommunikation (NFC) och Wi-Fi. Dessa tre valdes eftersom de stöds av nyare mobila plattformar idag. Kommunikations-protokollen analyserades sedan gentemot olika användningsområden inom IoT, eftersom påståendet vad som är bäst anpassat beror på vad situationen kräver för egenskaper. En systemutvecklare som ska välja kommunikationsprotokoll till en IoT-tillämpning och läser denna rapport bör själv jämföra de olika protokollen mot varandra inom de fem faktorerna för att kunna avgöra vilket protokoll som passar bäst inom dennes situation. I arbetet utfördes endast experimentella studier på BLE på grund av begränsningar inom utrustningen. Ytterligare experiment inom NFC och Wi-Fi skulle ge ett bredare perspektiv med fler infallsvinklar. / By studying different communication protocols respond to what it is that makes a certain protocol best suited for use between mobile devices and IoT devices. This study used a qualitative literature study to create a proper theoretical background and an experimental study where two theories were investigated in whether they matched wih the results from the reality. The five factors compatibility, battery loss, frequency, range and reliability were investigated in the communication protocols Bluetooth Low Energy (BLE), Near field communication (NFC) and Wi-Fi, these three because they are supported by newer mobile platforms today. The communication protocols were then analysed against various uses in the IoT, since the claim what it is that makes it best suited depends on what the situation requires. A system developer that is about to select the communication protocol to use in an IoT application and reads this study should compare the different protocols to each other within the five factors to determine which protocol is best suited for his situation. This study only performed experimental studies on BLE because of limitations in the equipment. Additional experiments on NFC and Wi-Fi would provide a wider perspective.

Imaging with THz radiation at nanoscale resolution is highly desirable for specific material investigations that cannot be obtained in other parts of the electromagnetic spectrum. Nevertheless, classical free-space focusing of THz waves is limited to a >100 μm spatial resolution, due to the diffraction limit. However, the scattering- type scanning near-field optical microscopy (s-SNOM) promises to break this diffraction barrier. In this work, the realization of s-SNOM and spectroscopy for the THz spectral region from 30–300 μm (1–10 THz) is presented. This has been accomplished by using two inherently different radiation sources at distinct experimental setups: A femtosecond laser driven photoconductive antenna, emitting pulsed broadband THz radiation from 0.2–2 THz and a free-electron laser (FEL) as narrow-band high-intensity source, tunable from 1.3–10 THz. With the photoconductive antenna system, it was demonstrated for the first time that near-field spectroscopy using broadband THz-pulses, is achievable. Hereby, Terahertz time-domain spectroscopy with a mechanical delay stage (THz-TDS) was realized to obtain spectroscopic s-SNOM information, with an additional asynchronous optical sampling (ASOPS) option for rapid far-field measurements. The near-field spectral capabilities of the microscope are demonstrated with measurements on gold and on variably doped silicon samples. Here it was shown that the spectral response follows the theoretical prediction according to the Drude and the dipole model. While the broadband THz-TDS based s-SNOM in principle allows for the parallel recording of the full spectral response, the weak average power of the THz source ultimately limits the technique to optically investigate selected sample locations only. Therefore, for true THz near-field imaging, a FEL as a high-intensity narrow- band but highly-tunable THz source in combination with the s-SNOM technique, has been explored. Here, the characteristic near-field signatures at wavelengths from 35–230 μm are shown. Moreover, the realization of material sensitive THz near-field imaging is demonstrated by optically resolving, a structured gold rod with a reso- lution of up to 60 nm at 98 μm wavelength. Not only can the gold be distinguished from the silica substrate but moreover parts of the structure have been identified to be residual resin from the fabrication process. Furthermore, in order to explore the resolution capabilities of the technique, the near-fields of patterned gold nano- structures (Fischer pattern) were imaged with a 50 nm resolution at wavelengths up to 230 μm (1.2 THz). Finally, the imaging of a topography-independent optical material contrast of embedded organic structures, at exemplary 150 μm wavelength is shown, thereby demonstrating that the recorded near-field signal alone allows us to identify materials on the nanometer scale. The ability to measure spectroscopic images by THz-s-SNOM, will be of benefit to fundamental research into nanoscale composites, nano-structured conductivity phenomena and metamaterials, and furthermore will enable applications in the chemical and electronics industries. / Die Bildgebung mit THz Strahlung im Nanobereich ist höchst wünschenswert für genaue Materialuntersuchungen, welche nicht in anderen Spektralbereichen durchgeführt werden kann. Aufgrund des Beugungslimits ist kann jedoch mit klassischen Methoden keine bessere Auflösung als etwa 100 μm für THz-Strahlung erreicht werden. Die Methode der Streulicht-Nahfeldmikroskopie (s-SNOM) verspricht jedoch dieses Beugungslimit zu durchbrechen. In der vorliegenden Arbeit wird die Realisierung der Nahfeld-Mikroskopie und Spektroskopie im THz-Spektralbereich von 30–1500 μm (0.2–10 THz) präsentiert. Dies wurde mittels zweier grundsätzlich unterschiedlichen Strahlungsquellen an separaten Experimentaufbauten erreicht: Einer photoleitenden Antenne welche gepulste breitbandige THz-Strahlung von 0.2–2 THz emittiert, sowie einem Freie- Elektronen Laser (FEL) als schmalbandige hochleistungs Quelle, durchstimmbar von 1.3–10 THz. Mit dem photoleitenden Antennensystem konnte zum ersten mal demonstriert werden, dass mit breitbandigen THz-Pulsen Nahfeldspektroskopie möglich ist. Dazu wurde die übliche THz-Time-Domain-Spektroskopie (THz-TDS) zur Erhaltung der spektroskopischen s-SNOM Informationen, sowie asynchrones optisches Abtasten (ASOPS) für schnelle Fernfeld Spektroskopie eingesetzt. Die nahfeldspektroskopischen Fähigkeiten des Mikroskops wurden anhand von Messungen an Gold sowie unterschiedlich dotierten Siliziumproben demonstriert. Dabei konnte gezeigt werden, dass die spektrale Antwort den theoretischen Voraussagen des Drude- sowie Dipol Modells folgt. Während das breitband THz-TDS basierte s-SNOM spektroskopische Nahfelduntersuchungen zulässt, limitiert jedoch die schwache Ausgangsleistung der THz-quelle diese Technik insofern, dass praktisch nur Punktspektroskopie an ausgesuchten Probenstellen möglich ist. Für echte nanoskopische Nahfeldbildgebung wurde daher ein FEL als durchstimmbare hochleistungs THz-Quelle in Kombination mit der s-SNOM-Technik erforscht. Hierzu wurden die charakteristischen Nahfeld-Signaturen bei Wellenlängen von 35–230 μm untersucht, gefolgt von die Verwirklichung materialsensitiver THz Nahfeldbildgebung gezeigt an Goldstreifen mit bis zu 60 nm Auflösung. Dabei kann nicht nur das Gold von dem Glassubstrat unterschieden werden, sondern auch Ablagerungen als Überreste des Fabrikationsprozesses identifiziert werden. Um die Grenzen der Auflösungsmöglichkeiten dieser Technik zu sondieren, wurden weiterhin die Nahfelder von gemusterten Gold-Nanostrukturen (Fischer-Pattern) bei Wellenlängen bis zu 230 μm (1.2 THz) abgebildet. Hierbei wurde eine Auflösung von 50 nm festgestellt. Schliesslich konnte der topographieunabhängige Materialkontrast von eingebetteten organischen Strukturen, exemplarisch bei 150 μm Wellenlänge, gezeigt werden. Die Fähigkeit, spektroskopische Aufnahmen mittels der THZ-s-SNOM Technik zu erzeugen, wird der Grundlagenforschung und in der Nanotechnologie zu Gute kommen, und weiterhin Anwendungen in der Chemischen- und Halbleiterindustrie ermöglichen.

Effective focusing of electromagnetic (EM) energy to nanoscale regions is one of the major challenges in nano-photonics and plasmonics. The strong localization of the optical energy into regions much smaller than allowed by the diffraction limit, also called nanofocusing, offers promising applications in nano-sensor technology, nanofabrication, near-field optics or spectroscopy. One of the most promising solutions to the problem of efficient nanofocusing is related to surface plasmon propagation in metallic structures. Metallic tapered rods, commonly used as probes in near field microscopy and spectroscopy, are of a particular interest. They can provide very strong EM field enhancement at the tip due to surface plasmons (SP’s) propagating towards the tip of the tapered metal rod. A large number of studies have been devoted to the manufacturing process of tapered rods or tapered fibers coated by a metal film. On the other hand, structures such as metallic V-grooves or metal wedges can also provide strong electric field enhancements but manufacturing of these structures is still a challenge. It has been shown, however, that the attainable electric field enhancement at the apex in the V-groove is higher than at the tip of a metal tapered rod when the dissipation level in the metal is strong. Metallic V-grooves also have very promising characteristics as plasmonic waveguides. This thesis will present a thorough theoretical and numerical investigation of nanofocusing during plasmon propagation along a metal tapered rod and into a metallic V-groove. Optimal structural parameters including optimal taper angle, taper length and shape of the taper are determined in order to achieve maximum field enhancement factors at the tip of the nanofocusing structure. An analytical investigation of plasmon nanofocusing by metal tapered rods is carried out by means of the geometric optics approximation (GOA), which is also called adiabatic nanofocusing. However, GOA is applicable only for analysing tapered structures with small taper angles and without considering a terminating tip structure in order to neglect reflections. Rigorous numerical methods are employed for analysing non-adiabatic nanofocusing, by tapered rod and V-grooves with larger taper angles and with a rounded tip. These structures cannot be studied by analytical methods due to the presence of reflected waves from the taper section, the tip and also from (artificial) computational boundaries. A new method is introduced to combine the advantages of GOA and rigorous numerical methods in order to reduce significantly the use of computational resources and yet achieve accurate results for the analysis of large tapered structures, within reasonable calculation time. Detailed comparison between GOA and rigorous numerical methods will be carried out in order to find the critical taper angle of the tapered structures at which GOA is still applicable. It will be demonstrated that optimal taper angles, at which maximum field enhancements occur, coincide with the critical angles, at which GOA is still applicable. It will be shown that the applicability of GOA can be substantially expanded to include structures which could be analysed previously by numerical methods only. The influence of the rounded tip, the taper angle and the role of dissipation onto the plasmon field distribution along the tapered rod and near the tip will be analysed analytically and numerically in detail. It will be demonstrated that electric field enhancement factors of up to ~ 2500 within nanoscale regions are predicted. These are sufficient, for instance, to detect single molecules using surface enhanced Raman spectroscopy (SERS) with the tip of a tapered rod, an approach also known as tip enhanced Raman spectroscopy or TERS. The results obtained in this project will be important for applications for which strong local field enhancement factors are crucial for the performance of devices such as near field microscopes or spectroscopy. The optimal design of nanofocusing structures, at which the delivery of electromagnetic energy to the nanometer region is most efficient, will lead to new applications in near field sensors, near field measuring technology, or generation of nanometer sized energy sources. This includes: applications in tip enhanced Raman spectroscopy (TERS); manipulation of nanoparticles and molecules; efficient coupling of optical energy into and out of plasmonic circuits; second harmonic generation in non-linear optics; or delivery of energy to quantum dots, for instance, for quantum computations.

In this work, scanning multiprobes microscopes were used to study the physical properties of biological, vitreous and ceramics samples. In particular, we have used three different scanning probe microscopy techniques to the study the samples. At first, an atomic force microscope was used to evaluate the mechanical properties of macrophages due to cell adhesion to an extracellular matrix and to study the changes in DNA molecules conformation treated with thymol and adsorbed onto a mica surface modified by poly-L-lysine. The results of these studies show that the cytoskeleton-mediated cell-matrix interactions directly affect biomechanical events in cells by modifying physical properties of the cytoskeleton and that the modification of mica surface using poly-L-Lysine provides a strong and firm bond with DNA. This strong fixation of DNA, allows the study of DNA conformational change on mica when interacting with tymol. The atomic force microscope was also used in studies of laser induced thermal expansion in commercial phosphate glasses. The ability of this technique to detect nanoscale surface deformations and the good agreement between theoretical and experimental results show the potential of this technique to study the amplitude and the dynamic of thermal effects in solid materials. In another study, conductive atomic force microscopy was used to analyze electrical properties of barium titanate semiconductor ceramic and their correlation with specific topographic features of the sample. Finally, using the scanning near-field optical microscopy, we studied interactions between cells and gold nanoparticles, without the need of fluorescent labeling on the nanoparticles, with high spatial resolution. During the presentation of these studies the challenges and necessary instrumentation for their realization was discussed. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Neste trabalho, microscópios de varredura multi-sondas foram utilizados para o estudo de propriedades físicas de amostras biológicas, vítreas e cerâmicas. Em especial, usamos três diferentes técnicas de microscopia de varredura por sonda no estudo destas amostras. Primeiramente, um microscópio de força atômica foi usado para avaliar os efeitos na mecânica da membrana de macrófagos, verificando a interferência da adesão celular por uma matriz extracelular. Em seguida, estudamos as mudanças de conformação de moléculas de DNA tratadas com Timol e adsorvidas sobre uma superfície de uma mica modificada por poli-L-lisina. Os resultados destes estudos implicam que as interações célula-MEC mediada pelo citoesqueleto afetam diretamente os eventos biomecânicos das membranas, modificando as propriedades físicas do citoesqueleto celular, e que a modificação da superfície da mica utilizando poli-L-Lisina proporciona uma ligação forte e firme com o DNA. Esta forte fixação do DNA, permitiu o estudo da mudança conformacional do DNA na mica quando interagindo com o timol. O microscópio de força atômica também foi usado para realizar de estudos da expansão térmica em vidros fosfatos comerciais, induzida por um laser. A capacidade desta técnica de detectar deformações superficiais em nano-escala e a boa concordância dos resultados teóricos e experimentais mostra o potencial desta técnica para o estudo da amplitude e dinâmica de efeitos térmicos em materiais sólidos. Num outro estudo, a microscopia força atômica condutora foi usada para a análise de propriedades elétricas de cerâmicas de titanato de bário semicondutor e suas correlações com características topográficas específicas da amostra. Por fim, estudamos interações entre células e nanopartículas de ouro, com o uso da microscopia de varredura em campo próximo, sem a necessidade de marcação fluorescente nas nanopartículas e com alta resolução espacial. Durante a apresentação de cada um destes estudos foi discutido os desafios e parte da instrumentação necessárias para a realização dos mesmos.

Submitted by Daniele Santos (danielesantos.htl@gmail.com) on 2017-02-21T21:04:19Z No. of bitstreams: 1 Eduardo.pdf: 1544695 bytes, checksum: ad700b85bc86a6f4889a9f52275ab887 (MD5) / Approved for entry into archive by Janete de Oliveira Feitosa (janete.feitosa@fgv.br) on 2017-02-23T17:38:59Z (GMT) No. of bitstreams: 1 Eduardo.pdf: 1544695 bytes, checksum: ad700b85bc86a6f4889a9f52275ab887 (MD5) / Made available in DSpace on 2017-03-02T13:43:19Z (GMT). No. of bitstreams: 1 Eduardo.pdf: 1544695 bytes, checksum: ad700b85bc86a6f4889a9f52275ab887 (MD5) Previous issue date: 2016-11-10 / Today there exist a myriad of different types of physical access control systems (PACS) that use a smart card or mobile device as a key. The mobile device enabled smart locks, as they are often referred to, operate using either Wi-Fi or Bluetooth. This thesis has explored the use of a third emerging wireless technology called Near Field Communication (NFC) available in mobile devices such as smartphones. Near Field Communication (NFC) technology is a relatively new technology that is on the rise and is included in almost every new mobile device. By leveraging Near Field Communication (NFC) enabled mobile devices, a highly secure access control system can be achieved and developed taking advantage of the computational power of smartphones in comparison to traditional methods the business implications are huge, Several different authentication and encryption protocols, mobile operating systems and Near Field Communication (NFC) modes of operation where analyzed and evaluated. After considerations technical considerations the Secure Remote Password authentication protocol on top of Near Field Communication (NFC) card emulation (CE) scheme with the client application running on smartphones operating system (OS) was selected. This thesis shows that Near Field Communication (NFC) enables a mobile device to act as a key in a secure access control system (PACS) and as the user base for NFC grows larger so will the likelihood that we will come to see more of these types of systems in business and organizations.

Dans le domaine des transactions et du paiement électronique avec une carte à puce, le standard de communication en champ proche « Near Field Communication » (NFC) s’est imposé comme la technologie des transactions sans contact mobiles sécurisées pour le paiement, le contrôle d’accès, ou l’authentification. Les services sans contact mobiles sécurisés sont basés sur le mode émulation de carte du standard NFC qui implique une composante matérielle à accès restreint de type carte à puce appelée « Secure Element » (SE) dans laquelle sont stockées les données confidentielles et les fonctions sensibles. Malgré les efforts de standardisation de l'écosystème, les modèles proposés pour la mise en œuvre du SE sont complexes et souffrent du manque de généricité, à la fois pour offrir des mécanismes d’abstraction, pour le développement d’applications de haut niveau, et pour la mise en œuvre et la vérification des contraintes de sécurité des applications.L’objectif de la thèse est de concevoir et réaliser un environnement logiciel basé sur un modèle générique compatible avec les standards établis et peu sensible aux évolutions technologiques. Cet environnement devrait permettre à des non-experts de développer des applications multiplateformes, multimodes, multi-facteurs de forme, qui s’interfacent avec le SE dans un smartphone NFC. / In the field of electronic transactions and payment with a smart card, the Near Field Communication (NFC) standard has stood out against other candidate technologies for secure mobile contactless transactions for payment, access control, or authentication. Secure mobile contactless services are based on the card emulation mode of the NFC standard which involves a smart card type component with restricted access called "Secure Element" (SE) in which sensitive data and sensitive functions are securely stored and run. Despite considerable standardization efforts around the SE ecosystem, the proposed models for the implementation of SE are complex and suffer from the lack of genericity, both to offer abstraction mechanisms, for the development of high-level applications, and for the implementation and verification of applications security constraints.The objective of the thesis is to design and realize a software environment based on a generic model that complies with established standards and which is not very sensitive to technological evolutions. This environment should enable non-experts to develop multi-platform, multi-mode, multi-factor SE-based applications running into the NFC smartphone.

Para o desenvolvimento da nanociência atual há forte demanda por equipamentos capazes de caracterizar sistemas em escalas da ordem nanométrica. Este contexto impulsionou o desenvolvimento de microscópios ópticos de varredura em campopróximo (Scanning Near-field Optical Microscope SNOM). Diferentemente da microscopia óptica tradicional, os SNOMs detectam a radiação eletromagnética evanescente e, conseqüentemente, a resolução não é limitada pelo critério de Rayleigh. No Laboratório de Materiais Magnéticos IFUSP desenvolvemos um SNOM sensível a efeitos Kerr magnetoópticos (MO-SNOM). Dessa maneira, associamos a alta resolução da técnica à alta sensibilidade dos efeitos magnetoópticos. Trata-se se uma área relativamente pouco explorada e carente de resultados sistemáticos na literatura. Utilizando o MO-SNOM, caracterizamos partículas microestruturadas de Co70.4Fe4.6Si15B10 amorfo com dimensões de 16x16x0.08 microm3 e 4x4x0.08 microm3. Os resultados compreendem dezenas de imagens de susceptibilidade magnetoóptica diferencial com resolução melhor que 200 nm e curvas de histerese local. Em primeira análise, a demonstração de resultados sistemáticos ajuda a estabelecer a técnica. O comportamento magnético das partículas, estudadas sob várias condições de campo aplicado, se mostrou determinado basicamente pela anisotropia de forma. As curvas de histerese local mostraram comportamentos intrinsecamente locais e motivaram uma interessante discussão sobre os parâmetros de caracterização magnética convencionais. As medidas realizadas indicam que o efeito Kerr magnetoótico transversal em campopróximo é similar ao campo-distante. Os resultados são fortemente sustentados por medidas de microscopia magnetoóptica de campo-distante, simulações micromagnéticas e medidas de microscopia de força magnética. Medidas complementares revelam o potencial do MO-SNOM para caracterizações de objetos extensos quanto a potenciais de pinning. Além disso, medidas em filmes finos de NiFe/FeMn acoplados por exchange-bias evidenciam a alta sensibilidade do MO-SNOM, estimada de DM ~ 2 x 10-12 emu. / To support nanosciences evolution, there is a strong demand for developing new instrumentation devoted to nano-scale characterization. In this context, the development of the Scanning Near-field Optical Microscope (SNOM) took place. In contrast to traditional optical microscopes, SNOM deals with evanescent electromagnetic radiation and, consequently, the resolution is no longer limited by the Rayleigh criterion. At Laboratório de Materiais Magnéticos (LMM) IFUSP a SNOM devoted to magneto-optical Kerr effect measurements (MO-SNOM) has been developed. The MOSNOM associates the high resolution of the near-field technique to the high sensibility of the magneto-optical Kerr effect. Near-field magneto-optical microscopy is not yet wellestablished and there is a lack of systematic results in the literature. Using the MO-SNOM, amorphous Co70.4Fe4.6Si15B10 particles with 16x16x0.08 microm3 and 4x4x0.08 microm3 dimensions were studied. With resolution better than 200 nm, several magneto-optical differential susceptibility images and local hysteresis loops were obtained. The systematic results uphold the establishment of this new technique. Under the different applied field conditions, the magnetic behavior of the particles was found to be determined by shape anisotropy. Local hysteresis loops presented shapes intrinsic of local field induced process. The unusual hystesesis loops motivated interesting discussion about the conventional magnetic parameters. The MO-SNOM measurements indicate that the near-field transverse magneto-optical Kerr effect is similar to the far-field case. The results are highly supported by far-field magneto-optical microscopy, micromagnetic simulations and magnetic force microscopy measurements. Complementary measurements indicate the MO-SNOM potential to extensive magnetic surface characterization related to pinning potential distribution. Furthermore, measurements on the exchange-bias coupled NiFe/FeMn thin films make evident the MO-SNOM high sensitivity, estimated to be DeltaM ~ 2 x 10-12 emu.

Ma thèse concerne le développent de systèmes ultra compactes auto-alignés et à faible coût intégréssur fibre optique monomode pour la collection fibrée de la luminescence locale. Dans un premiertemps, un axicon fibré auto-aligné (AXIGRIN) est proposé permettant de fournir la première imagerierésolue ultra-compacte fibrée de quantum dots PbS infrarouges. Ensuite, la première nano-imagerie(système entièrement fibrée) de quantum dots PbS uniques est réalisée à l’aide d’une nano-antenneà ouverture bowtie intégrée sur pointe fibrée. Enfin, le concept d’≪antenne cornet≫ nano-optiqueest proposé pour le couplage direct et efficace de la luminescence excitée par rayons X à une fibreoptique, dans le but de générer les premiers capteurs et dosimètres fibrés à rayons X. / My thesis is devoted to develop ultra-compact, plug-and-play and low-cost single-mode optical fibersystems for in-fiber luminescence collection. First, a new fiber self-aligned axicon is proposed toprovide the first resolved infrared fluorescence imaging of PbS quantum dots in far field. Then,all-fiber near-field imaging of single PbS quantum dots is achieved by double resonance bowtienano-aperture antenna (BNA) with nanometer resolution. Finally, the concept of fiber nano-opticalhorn antenna is proposed for in-fiber X-ray excited luminescence out-coupling, with the purpose ofgenerating the first generation of fiber X-ray sensors and dosimeters