On a réalisé la démonstration d'une commutation spatiale de données d'une entrée vers 64 sorties par voie tout optique. Les composants originaux utilises sont une matrice de modulateurs a puits quantiques multiples en technologie gaalas a 64 éléments et une structure bistable optique de même technologie. Le principal résultat est le fonctionnement complet du démonstrateur voie par voie a la fréquence d'horloge de 20mhz (taux d'erreur inférieur a 1%). Les limitations viennent de la stabilité du laser et des non uniformités lors de la croissance epitaxiale des composants.

Dans les conditions actuelles du marché, les entreprises dans les pays émergeants ont le choix entre une dette à court terme en monnaie locale et un financement à long terme en devise forte provenant de sources internationales pour financer leurs investissements à long terme. Ceci crée un gap de taux ou de change. Cette thèse se situe dans la continuité des travaux de recherche qui ont déjà étudié la question de la diversification des risques de change dans les marchés financiers matures. A la différence des approches existantes, cette recherche se concentre sur les monnaies des pays émergeants pour lesquels il n’existe pas ou peu d’instruments de couverture du risque de change et de taux. Le modèle proposé repose sur une conception fondamentalement différente des modèles de risque existants, cherchant à atténuer les risques internes grâce à la diversification du portefeuille, plutôt que par l’adéquation entre l'offre et la demande. Ceci en étudiant à la fois les corrélations entre les monnaies des pays des marchés émergeants constituées dans un portefeuille composé de monnaies des pays africains, asiatiques, sud-américains et d’Europe de l’Est ainsi que l’effet de la diversification sur la réduction du risque de marché. Le choix des monnaies n’a pas une incidence significative sur les résultats du moment que les limites régionales proposées sont respectées. L’objectif principal de cette thèse est de contribuer à la spécification et à l’identification d’un modèle de diversification des risques tout en démontrant que la constitution d’un portefeuille diversifié et non couvert des produits dérivés de change sur les monnaies des marchés émergents est une activité lucrative à long terme. En s’appuyant sur un Système d’Information performant, le model proposé tente de démontrer l’effet qu’auraient de tels produits de couverture sur la réduction du risque de crédit de l’emprunteur et par conséquent celui des bailleurs de fonds. Afin d’atteindre cet objectif, les différents risques liés à ces activités ont été définis tout en choisissant les méthodes pour une gestion efficace de ces risques ainsi que la modélisation d’expositions hypothétiques créées par cette activité. L’impact de la réduction de l’exposition au risque de marché par l’usage des produits de couverture du risque de change et de taux, sur le risque de crédit des entreprises dans les pays émergeants a aussi été modélisé. Les résultats de la simulation proposée montrent qu’une gestion optimale des risques de changes et de taux générés, à travers l’offre de couvertures sur les monnaies des pays émergeants, peut être une activité lucrative pour les banques car l’atténuation des risques peut se faire en diversifiant efficacement le portefeuille. / In current market conditions, companies in emerging markets have the choice between a short-term debt in local currency and a long-term hard currency financing from international sources to finance their long-term investments. This practice would create either an interest rate gap or a currency gap. As an extent of previous researches and studies covering the question of currency risks diversification in mature financial markets, this thesis is quite distinctive from the existing literature as it focuses on emerging market currencies for which there are little or no hedging options of currency and interest rate risks. The proposed model is based on a fundamentally different approach from existing risk models, seeking to mitigate risks internally through portfolio diversification, rather than by matching supply and demand. This, by analyzing both correlations between emerging market currencies in a portfolio composed of African, Asian, South American and Eastern Europe currencies and the effect of diversification on market risk reduction. The main objective of this thesis is to contribute to the specification and the identification of a risk diversification model while demonstrating that the establishment of a diversified portfolio of emerging market currencies not covered by the commercial banks is a lucrative business over the long-term. With an efficient information system, the proposed model attempts to demonstrate the effect that such hedging products would have on reducing the credit risk of borrowers and hence the lenders. To achieve this aim, the different risks associated with these activities have been identified while choosing the methods for their effective management as well as the modeling of hypothetical exposures created by this activity. The impact of reducing market risk exposure through the usage of interest rate and currency hedging products on the credit risk rating of companies in emerging countries has also been modeled. The current research claims that the choice of currencies does not significantly impact the results as long as the proposed regional limits are respected. The simulation’ results show that managing a diversified currency portfolio under an optimal risk management guidelines can be a lucrative business for banks as the risk mitigation can be effectively done through portfolio diversification.

This dissertation thesis consists of three essays on new EU foreign exchange markets (FX), i.e. the Czech koruna, Polish zloty and Hungarian forint. In the first two essays, the impact of foreign macroeconomic news announcements and central banks' monetary policy settings on the value and volatility of examined exchange rates is analyzed. In the third chapter, the conditional comovements and volatility spillovers on new EU FX markets is examined. The aim of this thesis is to contribute to the existing empirical literature by providing new evidence of the examined currencies during periods, which have not been examined yet (after the Global financial crisis (GFC), during the EU debt crisis and during currency interventions in the Czech Republic). The first essay (Chapter 2) examines the impact of Eurozone/Germany and US macroeconomic news announcements and monetary policy settings of the ECB and the Fed on the value of new EU member states' currencies. It is a complex analysis of 1-minute intraday dataset performed by event study methodology (ESM). We observe different reactions of exchange rates in pair with the US dollar on the US macroeconomic announcements and Euro-expressed FX rates on Germany macro news during the EU debt crisis and after it. We also provide evidence of leaking news, showing...

In the presented thesis thin praseodymia films on non-passivated and passivated Si(111) substrates were investigated. The first part deals with PDA of praseodymia films with fluorite structure under UHV conditions in the temperature region from RT to 600°C. Here, a sophisticated model of the annealing process of praseodymia films is established. This is done by detailed analysis of XRD measurements using the kinematic diffraction theory in combination with the analysis of GIXRD, XRR and SPA-LEED measurements. It is shown that the untreated films, which are oxidized in 1 atm oxygen to obtain fluorite structure, do not exhibit pure PrO2 stoichiometry as it was assumed before. Instead, they decompose into two laterally coexisting species exhibiting a PrO2 and a Pr6O11. oxide phase, respectively. These species are laterally pinned to the lattice parameter of bulk Pr6O11. Homogeneous oxide films with Pr6O11 phase can be observed after annealing at 100°C and 150°C. Here, lateral strain caused by the pinning of the species is minimized and an increase of the crystallite sizes is determined. If higher annealing temperatures are applied, the film decomposes again into two coexisting species. Finally, after annealing at 300°C, a mixed crystalline film with both Pr2O3 and Pr2O3+Delta oxide phases is formed, where Delta denotes a considerable excess of oxygen within the sesquioxide phase. Again the lateral strain increases due to the tendency of praseodymia phases to increase their lattice parameters during oxygen loss combined with the lateral pinning. This is accompanied by a decrease of crystallite sizes, which are afterwards comparable to those of the untreated films. Further annealing at temperatures above 300°C does not significantly change the structure of the oxide film. However, the increase of the amorphous Pr-silicate interface between Si substrate and oxide at the expense of the crystalline oxide can be observed after annealing at higher temperatures. Furthermore, an increased mosaic spread of the crystallites occurs, which reduces the lateral strain caused by the oxygen loss. Nevertheless, the crystalline structure is stable against further annealing up to temperatures of 600°C. Transportation of the sample under ambient conditions after annealing at 200°C and 300°C leads to the formation of an additional crystalline structure at the surface which cannot be allocated to any praseodymia phase and may be explained by the contamination of the topmost crystalline layers with Pr-hydroxides. The results obtained from praseodymia films annealed in 1 atm nitrogen show that these films are good candidates to form homogeneous oxide films with pure cub-Pr2O3 structure by subsequent annealing in UHV. Here, a single oxide species is already observed after annealing at 300°C by SPA-LEED measurements which is in contrast to praseodymia films with fluorite structure where higher annealing temperatures (600°C) are necessary. In this case, negative effects like interface growth or increased defect density (mosaics, grain boundaries) can be minimized. Investigations on oxygen plasma-treated praseodymia films to obtain pure PrO2 stoichiometry are presented in the second part. Oxygen plasma-treated samples are compared with samples oxidized in 1 atm oxygen regarding the structure of the crystalline film. For this purpose, XRR and XRD measurements are performed to get structural information of the oxide film, which can be used to identify the corresponding oxide phases. Here, significantly smaller lattice constants of the crystalline oxide species can be observed after plasma treatment, which points to the incorporation of additional oxygen atoms. This verifies former studies, where a higher oxidation state of the oxide film was found by XPS measurements and it shows that plasma-treated films exhibit a higher oxidation state than films oxidized in 1 atm oxygen due to the availability of reactive atomic oxygen in the plasma. Furthermore, the Pr-silicate interface between crystalline film and Si substrate is not increased during plasma treatment. In the last part of the presented thesis, first results from the epitaxy of praseodymia films on Cl-passivated Si substrates are shown. The aim is to suppress the Pr-silicate formation during the growth process. Thus, praseodymia films are grown on passivated and non-passivated substrates to compare the crystallinity of both samples using XSW and LEED measurements. The structure of the oxide films on Cl-passivated Si is determined afterwards by XRR. It is shown that crystalline films with cub-Pr2O3 structure and several nanometer thickness can be successfully grown on Cl-passivated substrates. Here, the Pr-silicate interface layer are restricted to a single mono-layer. In contrast, the films grown on non-passivated substrates are completely amorphous containing Pr-silicates and Pr-silicides.

Bakgrund: Biståndsorganisationer (NGOs) är verksamma i hela världen och exponeras följaktligen mot valutarisk. Organisationerna hanterar biståndsmedel i så väl vanliga som ovanliga valutor när de på olika sätt finansierar lokala samarbetspartners. Andelen forskning om hur biståndsorganisationer hanterar valutaköp och valutarisk är begränsad och denna studie avser att studera området ytterligare. Syfte: Studien ämnar att utifrån riskhanteringsteori samt best practice analysera problematiken kring exponeringen mot valutarisk för svenska NGOs samt dess biståndsmottagare. Syftet är även att på detta sätt kunna diskutera generella strategier för svenska NGOs valutahandel och valutariskhantering. Genomförande: Den kvalitativa ansatsen utgörs av informationsinhämtning i form av nio intervjuer som utformats efter teori samt tidigare studier. Genom fem intervjuer med svenska NGOs ges en bild av hur organisationernas processer och behov ser ut relaterat till valutariskhantering. Information om hur valutarisk- och valutahantering bedrivs i praktiken samt hur experter inom området ser på NGOs nuvarande hantering baseras på fyra intervjuer med aktörer inom valutarisk- och valutahantering. Studiens empiri från genomförda intervjuer analyseras med stöd i studiens teoretiska referensram samt tidigare studier. Slutsats: Studien visar att problematiken kring valutahandel och valutariskhantering är mer komplex än den verkar vid en första anblick samt att syftet med valutariskhantering skiljer sig mellan vinstdrivande företag och ideella organisationer. Det framgår även att NGOs i nuläget överför merparten av exponeringen mot valutarisk till motpart genom avtal och att NGOs med stor andel bunden finansiering inte har möjlighet att utförligt undersöka eller implementera valutariskhantering. Slutligen har ett antal strategier utvecklats för att mer kostnadseffektivt köpa valuta. / Background: Non-governmental organizations (NGOs) are active in most parts of the world and are consequently exposed to foreign exchange risk. The organizations manage aid funds in both common and uncommon types of currency when they in different ways finance local cooperation partners. The amount of previous research how aid organizations handle the management of currency trade and foreign exchange risk is limited and this study aims to examine the area further. Aim: The study aims to analyse the complex of problems regarding exposure to foreign exchange risk for both Swedish NGOs and their cooperation partners, to do so on the basis of foreign exchange risk theory and best practice. The aim is in such a way to discuss general strategies for currency trade and foreign exchange risk management for Swedish NGOs. Completion: The qualitative approach consists of nine interviews that have been designed in accordance with theory and previous research. A picture of the organizational processes and needs of Swedish NGOs regarding foreign exchange risk- and currency trade management was given by five interviews with NGOs. Information concerning how foreign exchange risk- and currency trade management is utilized in practice and how experts in the field perceive current management of NGOs was gathered from four interviews with actors within foreign exchange risk- and currency trade management. The empirical data is analysed on the basis of the theoretical framework and previous research. Conclusion: The study shows that the complex of problems regarding foreign exchange risk- and currency trade management are not as straightforward as at first glance. It also indicates that foreign exchange risk management differs between for-profit businesses and non-profit organizations. It appears that NGOs currently transfer all foreign exchange risk exposure to its counterpart through contracts. The investigation and implementation of foreign exchange risk management is not possible for NGOs with a large ratio of restricted funds. Finally a number of strategies have been developed for a more cost-effective currency trade.