A thesis on the study of the frequency response of a pneumatic system designed to provide pulsed flow for flow control applications is presented. The system consists of a high pressure air source, a high-frequency solenoid valve, a length of tube and a minor loss. The experiment mimics the pneumatic drive for our Coanda-Assisted Spray Manipulation actuator and applies to many flow control applications involving pulsed flow. Square wave signals of various frequency are fed to the solenoid valve. The flow at the exit of the system is measured with a single hot wire and compared to steady flow through the same geometry. The effect of the inlet pressure, tube length and the size of the minor loss is evaluated. These data are modeled using a Transmission Matrix Model. (60 pages)

Doctor of Philosophy / Department of Mechanical and Nuclear Engineering / Douglas S. McGregor / The low natural abundance and supply shortage of ³He has resulted in an increase in the cost of ³He. The increase in cost of ³He proportional counters has motived the development of low cost, high efficiency, low gamma-ray sensitivity alternative technologies. A recently developed alternative technology is the ⁶Li-based suspended foil microstrip neutron detector (SFMND) that combines the neutron-conversion and gamma-ray discrimination capabilities of ⁶Li foils with the mechanical robustness and electrical capabilities of microstrip electrodes. SFMNDs differ from Li-foil multi-wire proportional counters because the anode wires are replaced by a single microstrip electrode that improves the mechanical robustness, reduces the microphonic sensitivity, and allows for more ⁶Li foils to be incorporated within a smaller form factor. The first-ever SFMNDs containing one and five 96%-enriched, 75-µm thick ⁶Li foils were fabricated using a silicon microstrip electrode. Neutron-sensitivity testing was performed yielding measured intrinsic thermal-neutron detection efficiencies, εth, of 4.02 ± 0.04% and 14.58 ± 0.11%, respectively. High electrode capacitance and gain instability were exhibited by the silicon microstrip electrode during neutron-sensitivity testing that led to the search for an electrically-stable microstrip-electrode substrate. Schott Borofloat® 33 glass was identified as an electrically-stable substrate and microstrip electrodes were fabricated and characterized. The Schott Borofloat® 33 microstrip electrodes were electrically-stable for a minimum duration of time of approximately 23 hours and had capacitances over an order of magnitude less than the identically sized silicon microstrip electrodes. One- and five-foil SFMNDs were fabricated with a Schott Borofloat® 33 microstrip electrode. Using 96%-enriched, 75-µm thick ⁶Li foils, the one- and five-foil devices had maximum measured εth of 12.58 ± 0.15% and 29.75 ± 0.26%, respectively, with measured gamma-ray rejection ratios of 6.46 x 10⁻⁵ ± 4.32 x 10⁻⁷ and 7.96 x 10-5 ± 4.65 x 10-7 for a ¹³⁷Cs exposure rate of 50 mR hr⁻¹. Devices containing one, five, ten, and twenty 96%-enriched, 75-µm thick ⁶Li foils were simulated using MCNP6 and are theoretically capable of having εth of 18.36%, 54.08%, 65.43%, and 68.36%, respectively. The deviation between measured and simulated εth is suspected to occur due to the electric field strength distribution, electron attachment, microstrip-electrode capacitance, or any combination thereof and solutions for each of these suspected concerns are described.

Doctor of Philosophy / Department of Physics / Kristan L. Corwin / The focus of this research is improving the pulse output energy of a mid-IR pulsed acetylene-filled Hollow-core Optical Fiber Gas LASer (HOFGLAS) system. Pump pulses and acetylene molecules interact with each other inside hollow-core photonic crystal fiber that effectively confines light and allows for strong gain. This results in lasing at 3.11 μm and 3.17 μm lines based on population inversion of acetylene molecules, which are optically pumped at rotational-vibrational overtones near 1.5 μm using 1 ns pulse duration from an optical parametric amplifier (OPA). This acetylene laser operates with no cavity mirrors because of a high gain in a single pass configuration. There are few laser sources in the mid-IR region while there are many applications for having a laser source in this range such as remote sensing, hazardous chemical detection, and breath analysis. This adds to the importance of the acetylene-filled HOFGLAS system. Some of the applications like remote sensing require high power. So, we moved toward power scaling this laser system by optimizing the laser operation through maximizing the OPA alignment to improve its modal content using longer length of fiber to increase the interaction length and improving the beam quality of the mid-IR emissions. The highest pulse energy ever obtained in the 3 µm mid-IR region from the acetylene-filled HOFGLAS after applying the improvements is reported here (1.4 μJ). Higher mid-IR pulse energies can be achieved by improving the pulse energy achievable from the OPA pump source and working with longer pulse duration to decrease the bandwidth of the OPA. This operation demonstrates many novel properties of acetylene-filled pulsed mid-IR hollow-core fiber lasers. The excellent spatial beam quality at highest power and phenomenological scaling of saturation power and efficiency with pressure that we observe point to the promise of power scaling and motivate further development of numerical models of the laser for deeper insight into these effects. M² measurement method was used to examine spatial beam quality and it was found to be fiber-dependent. For the improved setup, M² was investigated at several input pump powers in addition to the reproducibility checks. M² of 1.14 at the maximum output power motivates for beam combining to scale to higher power. The independence of efficiency on pressure is an evidence for reaching higher mid-IR power at a pressure where saturation behavior does not exist. achieving the highest mid-IR power to date, 1.4 μJ, encourages for building higher power OPA to produce high power mid-IR emissions. Taken as a whole, this laser exhibits novel behavior that motivates both numerical/theoretical investigation and further efforts to scale to higher powers.

Ionizing radiation is often used within medicine for diagnosis and treatments. Because ionizingradiation can be harmful to the body, it is important to know how it affects the tissue. Dosimetryis the study of how ionizing radiation deposits energy in a material. To measure how much ionizingradiation is deposited in the body, gas-filled detectors are often used. An ionization chamber isa type of gas-filled detector and exists in different shapes and sizes, depending on what kind ofmeasurements it is made for. Because ionization chambers are relatively expensive, it is often notpossible to buy one for each type of measurement that is to be done. This results in ionizationchambers being used for measurements they are not optimized for. This report evaluates thepossibility of 3D printing ionization chambers to make it easier to optimize them for specificmeasurements. The process included creating models of ionization chambers using CAD-software,slicing them and then 3D printing them. The 3D printed models were then brought to the SwedishRadiation Safety Authority for measurements. The ionization chambers were connected to highvoltage, and exposed to ionizing radiation in the form of high-intensity gamma-ray fields. Theoutput current of the ionization chamber was measured, which is proportional to the field intensity.The results were similar to those of a commercial ionization chamber. The conclusion is that it ispossible to 3D print ionization chambers. However, to get more accurate results, the design has tobe further optimized and more measurements need to be done.

La fission nucléaire consiste en la brisure d'un noyau lourd, généralement un actinide, en deux noyaux plus légers (ou trois dans quelques rares cas). Ce phénomène a été découvert par Hahn et Strassman en 1938. Très rapidement Meitner et Frisch proposèrent une explication théorique pour ce processus à l'aide du modèle de la goutte liquide. Depuis les modèles n'ont cessé d'évoluer et de se complexifier à travers l'ajout de nouveaux mécanismes et l'observation de nouveaux phénomènes. L'amélioration des modèles est un enjeu important à la fois pour la compréhension fondamentale du processus de fission mais aussi pour les applications. En effet, le dimensionnement des réacteurs futurs s'appuie de plus en plus sur des simulations numériques. Il devient dès lors primordial de réduire les incertitudes associées aux données utilisées. Cela passe alors par la validation des hypothèses sous-jacentes des modèles de fission nucléaire.Dans le cadre de cette thèse, on s'intéresse à deux aspects de la fission nucléaire qui permettront de tester la robustesse des théories. L'un des aspects concerne l'étude des fragments de fission issus de la région de la symétrie à travers la mesure des rendements et des distributions en énergie cinétique. L'autre aspect étudié est le moment angulaire des fragments de fission.Afin d'accéder au moment angulaire des fragments de fission, l'une des possibilités est d'analyser les propriétés des particules promptes, qui est l'une des ambitions du projet FIPPS (FIssion Product Prompt gamma-ray Spectrometer). Une partie de ce travail a été de caractériser les propriétés des spectromètres magnétiques gazeux à travers des mesures expérimentales et le développement d'une simulation Monte Carlo.La seconde partie de ce travail a consisté en la mesure de rapports isomériques et en l'extraction de la distribution du moment angulaire des fragments de fission à l'aide d'un code de désexcitaiton nucléaire. La mesure d'un noyau doublement magique ($^{132}$Sn) permet de mettre en lumière les limites actuelles des modèles de fission.Enfin la dernière partie de ce travail porte sur la mesure des rendements et des distributions en énergie cinétique des fragments de fission. Certains modèles prédisent l'existence de modes dans la fission nucléaire. La région des masses symétriques est dès lors un lieu de choix pour vérifier la validité de ces affirmations.Il est à noter qu'en parallèle de ces études, un accent fort a été mis sur le développement de méthodes d'analyse s'appuyant sur des outils statistiques afin notamment d'améliorer l'évaluation des incertitudes expérimentales. / Nuclear fission consists in splitting a nucleus, in general an actinide, into smaller nuclei. Despite nuclear fission was discovered in 1939 by Hahn and Strassman, fission models cannot predict the fission observables with an acceptable accuracy for nuclear fuel cycle studies for instance. Improvement of fission models is an important issue for the knowledge of the process itself and for the applications. To reduce uncertainties of the nuclear data used in a nuclear reactor simulation, a validation of the models hypothesis is mandatory.In this work, two features of the nuclear fission were investigated in order to test the resistance of the theories. One aspect is the study of the symmetric fission fragments through the measurement of their yield and kinetic energy distribution. The other aspect is the study of the fission fragment angular momentum.Two techniques are available to assess the angular momentum of a fission fragment. The first one is to look at the properties of the prompt $gamma$. The new spectrometer FIPPS (FIssion Product Prompt gamma-ray Spectrometer), is currently under development at the ILL and will combine a fission filter with a large array of $gamma$ and neutron detectors in order to respond to these issues. The first part of this work is dedicated to the study of the properties of a Gas Filled Magnet (GFM) which is the type of fission filter considered for the FIPPS project.The second part of this work deals with the measurement of isomeric yields and evaluations of the angular momentum distribution of fission fragments. The study of the spherical nucleus $^{132}$Sn shed the light on the current limits of fission models.Finally, the last part of this work is about the measurement of the yields and kinetic energy distributions of symmetric fission fragments. Since models predict the existence of fission modes, the symmetry region is a suitable choice to investigate this kind of prediction.In parallel with all these studies, an emphasis on the development of new methods derived from statistical tools is achieved in order to better control the uncertainties and estimate the biases.

Two long-lived halogen radionuclides (36Cl, T1/2 = 301 kyr, and 129I, T1/2 = 15.7 Myr) have been studied by means of Accelerator Mass Spectrometry (AMS) at the Uppsala Tandem Laboratory. The 36Cl measurements in natural samples using a medium-sized tandem accelerator (~1 MeV/amu) have been considered. A gas-filled magnetic spectrometer (GFM) was proposed for the separation of 36Cl from its isobar, 36S. Semi-empirical Monte-Carlo ion optical calculations were conducted to define optimal conditions for separating 36Cl and 36S. A 180° GFM was constructed and installed at the dedicated AMS beam line. 129I has been measured in waters from the Arctic and North Atlantic Oceans. Most of the 129I currently present in the Earth's surface environment can be traced back to liquid and gaseous releases from the nuclear reprocessing facilities at Sellafield (UK) and La Hague (France). The anthropogenic 129I inventory in the central Arctic Ocean was found to increase proportionally to the integrated 129I releases from these reprocessing facilities. The interaction and origin of water masses in the region have been clearly distinguished with the help of 129I labeling. Predictions based on a compartment model calculation showed that the Atlantic Ocean and deep Arctic Ocean are the major sinks for the reprocessed 129I. The variability in 129I concentration measured in seawater along a transect from the Baltic Sea to the North Atlantic suggests strong enrichment in the Skagerrak–Kattegat basin. The 129I inventory in the Baltic and Bothnian Seas is equal to ~0.3% of the total liquid releases from the reprocessing facilities. A lake sediment core sampled in northeastern Ireland was analyzed for 129I to study the history of the Sellafield releases, in particular the nuclear accident of 1957. High 129I concentration was observed corresponding to 1990 and later, while no indication of the accident was found. The results of this thesis research clearly demonstrate the uniqueness and future potential of 129I as a tracer of processes in both marine and continental archives.

Lab measurements and Monte Carlo simulations have been carried out for the evaluation of the Straw-type detectors used in the NA62 experiment at CERN. In addition, analyses of experiment data was used in corrections to improve the reconstruction of particle tracks, ultimately leading to improved resolution of the detector system as a whole. 97.7 percent of the Straws were aligned to within 30 microns, quantified as the deviation from zero of the mean of the inherent residual distribution of each Straw. A drift time dependence on where along the Straw the particle ionized have been corrected for; before the correction the dependence was as big as 6 ns. A radius-drift time relation based on the leading edge timing distribution has been deduced and implemented. Upon implementation artifacts from the piecewise fits used became evident. An alternative approach using residuals has been put forward.

O propósito principal desta tese foi a implementação e estudo da geração de pulsos laser de femtossegundos em comprimentos de onda curtos (ultravioleta profundo, ultravioleta de vácuo e ultravioleta extremo) pela técnica de conversão de frequência em capilar preenchido com gás nobre. Esta técnica de conversão de frequência tem feito diversas contribuições nas últimas décadas para o avanço da geração de pulsos laser ultracurtos nesta região espectral. O desenvolvimento de tais fontes de luz coerente possui importantes implicações nos estudos de espectroscopia resolvida no tempo em átomos, moléculas e materiais. Através da implementação da técnica de conversão de frequência com casamento de fase em capilar preenchido com gás argônio, foi possível a obtenção de pulsos de femtossegundos centrados em 260 nm e 195 nm utilizando um sistema laser amplificado Ti: safira (780 nm, 1.5 mJ, 43 fs, 1 KHz). Estes comprimentos de onda correspondem, respectivamente, aos terceiro e quarto harmônicos da frequência fundamental do laser utilizado. Pulsos centrados em 260 nm com excelente perfil espacial, energias da ordem de microjoules e durações temporais tão curtas quanto 18 fs, possibilitadas pela recompressão por um par de prismas, foram obtidos, os quais possuem grande aplicabilidade em estudos de espectroscopia não linear e resolvida no tempo. Pulsos ultracurtos centrados em 195 nm também foram obtidos. Uma investigação da influência da modulação da fase espectral do pulso laser em 780 nm sobre a geração de harmônicos através do processo do mistura de quatro ondas, também foi realizada. Desta forma, foi implementado um sistema de controle de formato de pulso laser de femtossegundo na configuração 4f baseado em um modulador espacial de luz de cristal líquido com o objetivo de modular a fase espectral dos pulsos laser em 780 nm. Este sistema de controle de formato de pulso foi então integrado ao sistema de geração de pulsos ultracurtos no ultravioleta profundo através do processo de mistura de ondas já implementado. Este estudo teve como objetivo, a obtenção da modulação indireta da fase espectral de pulsos em 260 nm através da transferência de fase espectral modulada de pulsos em 780 nm. Resultados iniciais interessantes foram obtidos utilizando uma fase espectral do tipo degrau com amplitude radianos, indicando a correta implementação do sistema. A obtenção de pulsos laser de femtossegundos no ultravioleta profundo com fase espectral modulada é de grande interesse para realização de experimentos de controle coerente nesta região espectral e também para estudos básicos de como a transferência de fase espectral ocorre para diferentes processos ópticos não lineares. Experimentos de geração de altos harmônicos pela técnica de conversão de frequência com casamento de fase em capilar preenchido com gás nobre, utilizando pulsos laser de femtossegundos em 400nm e 800nm, foram realizados durante estágio na Universidade do Colorado, EUA. Neste estudo, utilizando pulsos em 400nm, foi obtido um aumento maior que uma ordem de grandeza na região espectral em torno de 60eV em comparação com o fluxo de harmônicos gerados, nesta mesma região de energia, com pulsos centrados em 800nm. Por fim, através da experiência adquirida durante este estágio, foi desenvolvido e implementado em nosso laboratório um sistema de geração de altos harmônicos na região do ultravioleta extremo, baseado na técnica de conversão em capilar preenchido com gás argônio. Harmônicos de alta ordem na região de energia de 40ev (31nm) foram obtidos, tendo sido demonstrada a conversão sob condição de casamento de fase. Utilizando pulsos de femtossegundos em 780nm, a ordem máxima do harmônico observada foi igual a 27 (28.9nm, 42.9eV), devido a limitação da faixa espectral do monocromador utilizado em nossos experimentos. A implementação deste sistema torna disponível no Grupo de Fotônica, uma fonte de luz coerente no ultravioleta extremo, cujas propriedades únicas já tem sido amplamente exploradas em uma variedade de estudos de ciência básica e aplicada. / The main purpose of this thesis was the implementation and study of femtosecond laser pulses generation at short wavelengths (deep ultraviolet, vacuum ultraviolet end extreme ultraviolet) by the technique of frequency conversion in a hollow fiber filled with a noble gas. This frequency conversion technique has made several contributions in the last decades to improve the generation of ultrashort laser pulses in this spectral region. The development of such coherent light sources has important implications on ultrafast time-resolved spectroscopic study of atoms, molecules and materials. Through the implementation of the technique of phase matched frequency conversion in a gas filled hollow fiber using argon, it was possible to obtain femtosecond pulses centered at 260 nm and 195 nm using a Ti: sapphire amplified laser (780 nm, 1.5 mJ, 43 fs, 1 KHz). These wavelengths corresponds, respectively, to the third and fourth harmonics of the laser fundamental frequency. Pulses centered at 260 nm with excellent spatial profile, energies on the order of microjoules and temporal durations down to 18 fs, trough the compression by a prism pair, were obtained, which have wide applicability in nonlinear and time resolved optical spectroscopic studies. Ultrashort pulses at 195 nm where also obtained. An investigation of the influence of the spectral phase modulation of the laser pulses at 780 nm on the four-wave mixing nonlinear process for harmonic generation was also performed. In this way, a femtosecond pulse shaper based on a liquid crystal spatial light modulator in the 4f configuration was implemented in order to modulate the spectral phase of femtosecond pulses at 780 nm. This pulse shaper was then integrated to the system for generation of ultrashort pulses in the deep ultraviolet through the wave mixing process already implemented. This study aimed to obtain the indirect modulation of the 260 nm pulses spectral phase through the transfer of modulated spectral phase from pulses at 780 nm. Interesting initial results were obtained using a -step spectral phase, indicating the correct implementation of the system. The achievement of femtosecond pulses with modulated spectral phase in the deep ultraviolet is of great interest to perform coherent control studies in this spectral range and also for basic studies of how the spectral phase transfer occurs with different nonlinear optical laser processes. High-harmonic generation experiments based in the phase-matched frequency conversion in noble gas filled hollow fiber technique, using femtosecond pulses at 400 nm and 800 nm, were carried out during a internship at University of Colorado, USA. In this study, using pulses at 400 nm, an increase higher than one order of magnitude was obtained in the spectral region of 60 eV compared to harmonics generated, in this same region, with pulses at 800 nm. Finally, through the experience obtained during this internship, were carried out in our laboratory the development and implementation of a high harmonic generation system, based on the frequency conversion in a hollow fiber filled with argon gas. High harmonics with energies around 40eV (31nm) were obtained, and the conversion under phase-matched condition was demonstrated. Using pulses centered at 780nm, the highest harmonic order measured was 27 (28.9nm, 42.9eV), due to the spectral range limitation of monochromator used in our experiments. With the implementation of this system, becomes available at the Photonics Group a coherent light source at extreme ultraviolet wavelengths, which the unique properties have been already widely explored on a diversity of fundamental studies in basic and applied science.

O propósito principal desta tese foi a implementação e estudo da geração de pulsos laser de femtossegundos em comprimentos de onda curtos (ultravioleta profundo, ultravioleta de vácuo e ultravioleta extremo) pela técnica de conversão de frequência em capilar preenchido com gás nobre. Esta técnica de conversão de frequência tem feito diversas contribuições nas últimas décadas para o avanço da geração de pulsos laser ultracurtos nesta região espectral. O desenvolvimento de tais fontes de luz coerente possui importantes implicações nos estudos de espectroscopia resolvida no tempo em átomos, moléculas e materiais. Através da implementação da técnica de conversão de frequência com casamento de fase em capilar preenchido com gás argônio, foi possível a obtenção de pulsos de femtossegundos centrados em 260 nm e 195 nm utilizando um sistema laser amplificado Ti: safira (780 nm, 1.5 mJ, 43 fs, 1 KHz). Estes comprimentos de onda correspondem, respectivamente, aos terceiro e quarto harmônicos da frequência fundamental do laser utilizado. Pulsos centrados em 260 nm com excelente perfil espacial, energias da ordem de microjoules e durações temporais tão curtas quanto 18 fs, possibilitadas pela recompressão por um par de prismas, foram obtidos, os quais possuem grande aplicabilidade em estudos de espectroscopia não linear e resolvida no tempo. Pulsos ultracurtos centrados em 195 nm também foram obtidos. Uma investigação da influência da modulação da fase espectral do pulso laser em 780 nm sobre a geração de harmônicos através do processo do mistura de quatro ondas, também foi realizada. Desta forma, foi implementado um sistema de controle de formato de pulso laser de femtossegundo na configuração 4f baseado em um modulador espacial de luz de cristal líquido com o objetivo de modular a fase espectral dos pulsos laser em 780 nm. Este sistema de controle de formato de pulso foi então integrado ao sistema de geração de pulsos ultracurtos no ultravioleta profundo através do processo de mistura de ondas já implementado. Este estudo teve como objetivo, a obtenção da modulação indireta da fase espectral de pulsos em 260 nm através da transferência de fase espectral modulada de pulsos em 780 nm. Resultados iniciais interessantes foram obtidos utilizando uma fase espectral do tipo degrau com amplitude radianos, indicando a correta implementação do sistema. A obtenção de pulsos laser de femtossegundos no ultravioleta profundo com fase espectral modulada é de grande interesse para realização de experimentos de controle coerente nesta região espectral e também para estudos básicos de como a transferência de fase espectral ocorre para diferentes processos ópticos não lineares. Experimentos de geração de altos harmônicos pela técnica de conversão de frequência com casamento de fase em capilar preenchido com gás nobre, utilizando pulsos laser de femtossegundos em 400nm e 800nm, foram realizados durante estágio na Universidade do Colorado, EUA. Neste estudo, utilizando pulsos em 400nm, foi obtido um aumento maior que uma ordem de grandeza na região espectral em torno de 60eV em comparação com o fluxo de harmônicos gerados, nesta mesma região de energia, com pulsos centrados em 800nm. Por fim, através da experiência adquirida durante este estágio, foi desenvolvido e implementado em nosso laboratório um sistema de geração de altos harmônicos na região do ultravioleta extremo, baseado na técnica de conversão em capilar preenchido com gás argônio. Harmônicos de alta ordem na região de energia de 40ev (31nm) foram obtidos, tendo sido demonstrada a conversão sob condição de casamento de fase. Utilizando pulsos de femtossegundos em 780nm, a ordem máxima do harmônico observada foi igual a 27 (28.9nm, 42.9eV), devido a limitação da faixa espectral do monocromador utilizado em nossos experimentos. A implementação deste sistema torna disponível no Grupo de Fotônica, uma fonte de luz coerente no ultravioleta extremo, cujas propriedades únicas já tem sido amplamente exploradas em uma variedade de estudos de ciência básica e aplicada. / The main purpose of this thesis was the implementation and study of femtosecond laser pulses generation at short wavelengths (deep ultraviolet, vacuum ultraviolet end extreme ultraviolet) by the technique of frequency conversion in a hollow fiber filled with a noble gas. This frequency conversion technique has made several contributions in the last decades to improve the generation of ultrashort laser pulses in this spectral region. The development of such coherent light sources has important implications on ultrafast time-resolved spectroscopic study of atoms, molecules and materials. Through the implementation of the technique of phase matched frequency conversion in a gas filled hollow fiber using argon, it was possible to obtain femtosecond pulses centered at 260 nm and 195 nm using a Ti: sapphire amplified laser (780 nm, 1.5 mJ, 43 fs, 1 KHz). These wavelengths corresponds, respectively, to the third and fourth harmonics of the laser fundamental frequency. Pulses centered at 260 nm with excellent spatial profile, energies on the order of microjoules and temporal durations down to 18 fs, trough the compression by a prism pair, were obtained, which have wide applicability in nonlinear and time resolved optical spectroscopic studies. Ultrashort pulses at 195 nm where also obtained. An investigation of the influence of the spectral phase modulation of the laser pulses at 780 nm on the four-wave mixing nonlinear process for harmonic generation was also performed. In this way, a femtosecond pulse shaper based on a liquid crystal spatial light modulator in the 4f configuration was implemented in order to modulate the spectral phase of femtosecond pulses at 780 nm. This pulse shaper was then integrated to the system for generation of ultrashort pulses in the deep ultraviolet through the wave mixing process already implemented. This study aimed to obtain the indirect modulation of the 260 nm pulses spectral phase through the transfer of modulated spectral phase from pulses at 780 nm. Interesting initial results were obtained using a -step spectral phase, indicating the correct implementation of the system. The achievement of femtosecond pulses with modulated spectral phase in the deep ultraviolet is of great interest to perform coherent control studies in this spectral range and also for basic studies of how the spectral phase transfer occurs with different nonlinear optical laser processes. High-harmonic generation experiments based in the phase-matched frequency conversion in noble gas filled hollow fiber technique, using femtosecond pulses at 400 nm and 800 nm, were carried out during a internship at University of Colorado, USA. In this study, using pulses at 400 nm, an increase higher than one order of magnitude was obtained in the spectral region of 60 eV compared to harmonics generated, in this same region, with pulses at 800 nm. Finally, through the experience obtained during this internship, were carried out in our laboratory the development and implementation of a high harmonic generation system, based on the frequency conversion in a hollow fiber filled with argon gas. High harmonics with energies around 40eV (31nm) were obtained, and the conversion under phase-matched condition was demonstrated. Using pulses centered at 780nm, the highest harmonic order measured was 27 (28.9nm, 42.9eV), due to the spectral range limitation of monochromator used in our experiments. With the implementation of this system, becomes available at the Photonics Group a coherent light source at extreme ultraviolet wavelengths, which the unique properties have been already widely explored on a diversity of fundamental studies in basic and applied science.