RF-sputter fabrication of magnetic garnet thin films and simulation modeling for 1-D magnetic photonic crystal waveguide devices

One dimensional magnetic photonic crystals (1D-MPC) are promising structures for integrated optical isolator applications. Rare earth substituted garnet thin films with proper Faraday rotation are required to fabricate planar 1D-MPCs. In this thesis, flat-top response 1D-MPC was proposed and spectral responses and Faraday rotation were modeled. Bismuth substituted iron garnet films were fabricated by RF magnetron sputtering and structures, compositions, birefringence and magnetooptical properties were studied. Double layer structures for single mode propagation were also fabricated by sputtering for the first time. Multilayer stacks with multiple defects (phase shift) composed of Ce-YIG and GGG quarter-wave plates were simulated by the transfer matrix method. The transmission and Faraday rotation characteristics were theoretically studied. It is found that flat-top response, with 100% transmission and near 45o rotation is achievable by adjusting the inter-defect spacing, for film structures as thin as 30 to 35 μm. This is better than 3-fold reduction in length compared to the best Ce-YIG films for comparable rotations, thus allows a considerable reduction in size in manufactured optical isolators. Transmission bands as wide as 7nm were predicted, which is considerable improvement over 2 defects structure. Effect of repetition number and ratio factor on transmission and Faraday rotation ripple factors for the case of 3 and 4 defects structure has been discussed. Diffraction across the structure corresponds to a longer optical path length. Thus the use of guided optics is required to minimize the insertion losses in integrated devices. This part is discussed in chapter 2 in this thesis. Bismuth substituted iron garnet thin films were prepared by RF magnetron sputtering. We investigated or measured the deposition parameters optimization, crystallinity, surface morphologies, composition, magnetic and magnetooptical properties. A very high crystalline quality garnet film with smooth surface has been heteroepitaxially grown on (111) GGG substrate for films less than 1μm. Dual layer structures with two distinct XRD peaks (within a single sputtered film) start to develop when films exceed this thickness. The development of dual layer structure was explained by compositional gradient across film thickness, rather than strain gradient proposed by other authors. Lower DC self bias or higher substrate temperature is found to help to delay the appearance of the 2nd layer. The deposited films show in-plane magnetization, which is advantageous for waveguide devices application. Propagation losses of fabricated waveguides can be decreased by annealing in an oxygen atmosphere from 25dB/cm to 10dB/cm. The Faraday rotation at λ=1.55μm were also measured for the waveguides. FR is small (10° for a 3mm long waveguide), due to the presence of linear birefringence. This part is covered in chapter 4. We also investigated the elimination of linear birefringence by thickness tuning method for our sputtered films. We examined the compressively and tensilely strained films and analyze the photoelastic response of the sputter deposited garnet films. It has been found that the net birefringence can be eliminated under planar compressive strain conditions by sputtering. Bi-layer GGG on garnet thin film yields a reduced birefringence. Temperature control during the sputter deposition of GGG cover layer is critical and strongly influences the magnetization and birefringence level in the waveguide. High temperature deposition lowers the magnetization and increases the linear birefringence in the garnet films. Double layer single mode structures fabricated by sputtering were also studied. The double layer, which shows an in-plane magnetization, has an increased RMS roughness upon upper layer deposition. The single mode characteristic was confirmed by prism coupler measurement. This part is discussed in chapter 5.

Application of the maximum entropy method to the (2 + 1)D four-fermion model

We investigate spectral functions extracted using the maximum entropy method from correlators measured in lattice simulations of the (2+1)-dimensional four-fermion model. This model is particularly interesting because it has both a chirally broken phase with a rich spectrum of mesonic bound states and a symmetric phase where there are only resonances. In the broken phase we study the elementary fermion, pion, sigma, and massive pseudoscalar meson; our results confirm the Goldstone nature of the π and permit an estimate of the meson binding energy. We have, however, seen no signal of σ→ππ decay as the chiral limit is approached. In the symmetric phase we observe a resonance of nonzero width in qualitative agreement with analytic expectations; in addition the ultraviolet behavior of the spectral functions is consistent with the large nonperturbative anomalous dimension for fermion composite operators expected in this model.

The entropy conjecture for partially hyperbolic diffeomorphisms with 1-D center

We prove that if f is a partially hyperbolic diffeomorphism on the compact manifold M with one dimensional center bundle, then the logarithm of the spectral radius of the map induced by f on the real homology groups of M is smaller or equal to the topological entropy of f. This is a particular case of the Shub's entropy conjecture, which claims that the same conclusion should be true for any C1 map on any compact manifold.

Determination of 13C/12C ratios of endogenous urinary 5-amino-imidazole-4-carboxamide 1-D-ribofuranoside (AICAR)

RATIONALE: AICAR (5-aminoimidazole-4-carboxamide 1β-D-ribofuranoside) is prohibited in sport according to rules established by the World Anti-Doping Agency. Doping control laboratories identify samples where AICAR abuse is suspected by measuring its urinary concentration and comparing the observed level with naturally occurring concentrations. As the inter-individual variance of urinary AICAR concentrations is large, this approach requires a complementary method to unambiguously prove the exogenous origin of AICAR. Therefore, a method for the determination of carbon isotope ratios (CIRs) of urinary AICAR has been developed and validated. METHODS: Concentrated urine samples were fractionated by means of liquid chromatography for analyte cleanup. Derivatization of AICAR yielding the trimethylsilylated analog was necessary to enable CIR determinations by gas chromatography/combustion/isotope ratio mass spectrometry. The method was tested for its repeatability and stability over time and a linear mixing model was applied to test for possible isotopic discrimination. A reference population of n = 63 males and females was investigated to calculate appropriate reference limits to differentiate endogenous from exogenous urinary AICAR. These limits were tested by an AICAR elimination study. RESULTS: The developed method fulfills all the requirements for adequate sports drug testing and was found to be fit for purpose. The investigated reference population showed a larger variability in the CIR of AICAR than of the endogenous steroids. Nevertheless, the calculated thresholds for differences between AICAR and endogenous steroids can be applied straightforwardly to evaluate suspicious doping control samples with the same statistical confidence as established e.g. for testosterone misuse. These thresholds enabled the detection of a single oral AICAR administration for more than 40 h. CONCLUSIONS: Determination of thee CIRs is the method of choice to distinguish between an endogenous and an exogenous source of urinary AICAR. The developed method will enable investigations into doping control samples with elevated urinary concentrations of AICAR and clearly differentiate between naturally produced/elevated and illicitly administered AICAR.

Informe sobre el I Encuentro Británico-Español de Profesores de Biblioteconomía y Documentación, 2000 (Barcelona, 30-31 de març i 1 d'abril de 2000)

Sota el títol de Biblioteconomía y Documentación en la era digital: docencia e investigación, l'Observatori de la Comunicació Científica, la Secció Científica de Biblioteconomia i Documentació del Departament de Ciències Polítiques i Socials i l'Institut de Lingüística Aplicada (IULA) de la Universitat Pompeu Fabra organitzaren en les dates ja esmentades el I Encuentro Británico-Español de Profesores de Biblioteconomia y Documentación a la seu de la Rambla d'aquesta Universitat. Han col·laborat en aquesta activitat, a més, el Ministerio de Educación y Cultura, el Departamento de Biblioteconomía y Documentación de la Universidad Carlos III de Madrid, la Llicenciatura en Documentació de la Universitat Autònoma de Barcelona, la Llicenciatura en Documentació de la Universitat de Barcelona, la Llicenciatura en Documentació de laUniversitat Oberta de Catalunya, el Col·legi Oficial de Bibliotecaris-Documentalistes de Catalunya (COBDC) i la School of Information and Media Robert Gordon University. Pel nombre d'institucions implicades i pelseu alt nivell, es constata fàcilment que la trobada naixia amb molt bons auguris.

XI Congrés d'Historia de la Medicina Catalana, 29 de setembre a 1 d`octubre de 2000. Programa

Aquesta publicació conté el programa d'activitats previst per l'XIè Congrés d'Història de Medicina Catalana, cel·lebrat a l'edifici de la Reial Acadèmia de Medicina de Catalunya. També conté una petita història i descripció de la seu del congrés.

Balladi op. 10 no. 1 d

Soitinnus: piano.

[4 phot. de monuments musulmans en France, 3 du cimetière musulman au Père-Lachaise à Paris, 1 d'une gravure représentant la mosquée Mahomet à Buzancy (Ardennes), le tout dû à la Photogravure parisienne de monuments historiques, 30, boulevard Saint-Germain. Des collections du prince R. Bonaparte]

Donateur : Bonaparte, Roland (1858-1924)

Arrêt du conseil d'Etat qui ordonne que des 500000 liv. d'augmentations de gages créées par édit d'octobre 1710 distraction sera faite de 797 l. 6 s. 1 d. pour être distribués aux offices de conseillers-secrétaires de S. M. et autres officiers des chancelleries établies près les parlements, cours supérieures et présidiaux du royaume en exécution de l'Edit du mois d'oct. 1704

[Acte. 1711-10-20. Versailles]