Amplification Properties of Femtosecond Laser-Written Er3+/Yb3+ Doped Waveguides in a Tellurium-Zinc Glass

We report on the fabrication and characterization of active waveguides in a TeO2-ZnO glass sample doped with Er3+/Yb3+ fabricated by direct laser writing with a femtosecond laser delivering 150 fs pulses at 1 kHz repetition rate. The waveguides exhibit an internal gain of 0.6 dB/cm at 1535 nm, thus demonstrating the feasibility of active photonics lightwave circuits and lossless components in such a glass composition

Enhanced Optical Properties of Germanate and Tellurite Glasses Containing Metal or Semiconductor Nanoparticles

Germanium- and tellurium-based glasses have been largely studied due to their recognized potential for photonics. In this paper, we review our recent studies that include the investigation of the Stokes and anti-Stokes photoluminescence (PL) in different glass systems containing metallic and semiconductor nanoparticles (NPs). In the case of the samples with metallic NPs, the enhanced PL was attributed to the increased local field on the rare-earth ions located in the proximity of the NPs and/or the energy transfer from the metallic NPs to the rare-earth ions. For the glasses containing silicon NPs, the PL enhancement was mainly due to the energy transfer from the NPs to the Er3+ ions. The nonlinear (NL) optical properties of PbO-GeO2 films containing gold NPs were also investigated. The experiments in the pico- and subpicosecond regimes revealed enhanced values of the NL refractive indices and large NL absorption coefficients in comparison with the films without gold NPs. The reported experiments demonstrate that germanate and tellurite glasses, having appropriate rare-earth ions doping and NPs concentration, are strong candidates for PL-based devices, all-optical switches, and optical limiting

Project, construction and testing of the system Magnets main accelerator of microtron booster IFUSP

O presente trabalho teve como objetivo: projetar, construir e testar os imas principais do acelerador race-track microtron booster do ifusp, que tem como funcao defletir e focalizar o feixe de eletrons, permitindo a sua recirculacao. Esses imas desempenham papel fundamental quanto a qualidade do feixe obtido que, por sua vez, constitui um fator primordial para experiencias em fisica nuclear. O trabalho desenvolve a teoria do funcionamento do acelerador e os calculos analiticos que fundamentam a geometria dos imas. A ausencia da uniformidade do campo magnetico e a presenca de campos de borda inadequados comprometem o sincronismo. Utilizou-se bobinas corretoras confeccionadas na forma de circuitos impressos, que limitaram a falta de uniformidade a valores relativos de campo magnetico da ordem de \'10 POT.-5\'. Os imas possuem pecas polares auxiliares (clamps) que criam campos de borda reversos ao campo principal. Os clamps foram projetados por meio de simulacoes realizadas com os programas poisson e ptrace, de forma a se obter uma distribuicao para o campo magnetico que propicie aceleracao para uma distancia conveniente entre os imasThe present work had the purpose of designing, building and testing the bending magnets of the IFUSP race-track microtron booster that deflect and focus the electron beam and allow its recirculation. These magnets play a fundamental role in terms of the beam quality, which is important in Nuclear Physics research. This work develops the theory conceming the functioning of the accelerator and the analytical calculations that establish the geometry ofthe magnets. The lack of magnetic field uniformity and the presence of inadequate fringing fields damage the synchronism. The magnetic fields were corrected using coils made of etched printed circuit boards. This method provides uniformity of a few parts in 10 \'10 POT.-5\' . The magnets have auxiliary poles (clamps) that produce reverse fringing fields. The clamps were designed using Poisson and Ptrace programs in order to get a magnetic field distribution that allows acceleration for a convenient distance between the magnets. The beam trajectories determined by Ptrace program were confirmed with agreement of 0,1% using the floating wire technique

Design, construction and testing of a set of corrector coils for homogenization of the field of a dipole magnet

Projeto, construção e teste de um conjunto de bobinas corretoras para homogeneização do campo de um imã dipolarDesign, construction and testing of a set of corrector coils for homogenization of the field of a dipole magne

Project, construction and testing of the system Magnets main accelerator of microtron booster IFUSP

O presente trabalho teve como objetivo: projetar, construir e testar os imas principais do acelerador race-track microtron booster do ifusp, que tem como funcao defletir e focalizar o feixe de eletrons, permitindo a sua recirculacao. Esses imas desempenham papel fundamental quanto a qualidade do feixe obtido que, por sua vez, constitui um fator primordial para experiencias em fisica nuclear. O trabalho desenvolve a teoria do funcionamento do acelerador e os calculos analiticos que fundamentam a geometria dos imas. A ausencia da uniformidade do campo magnetico e a presenca de campos de borda inadequados comprometem o sincronismo. Utilizou-se bobinas corretoras confeccionadas na forma de circuitos impressos, que limitaram a falta de uniformidade a valores relativos de campo magnetico da ordem de \'10 POT.-5\'. Os imas possuem pecas polares auxiliares (clamps) que criam campos de borda reversos ao campo principal. Os clamps foram projetados por meio de simulacoes realizadas com os programas poisson e ptrace, de forma a se obter uma distribuicao para o campo magnetico que propicie aceleracao para uma distancia conveniente entre os imasThe present work had the purpose of designing, building and testing the bending magnets of the IFUSP race-track microtron booster that deflect and focus the electron beam and allow its recirculation. These magnets play a fundamental role in terms of the beam quality, which is important in Nuclear Physics research. This work develops the theory conceming the functioning of the accelerator and the analytical calculations that establish the geometry ofthe magnets. The lack of magnetic field uniformity and the presence of inadequate fringing fields damage the synchronism. The magnetic fields were corrected using coils made of etched printed circuit boards. This method provides uniformity of a few parts in 10 \'10 POT.-5\' . The magnets have auxiliary poles (clamps) that produce reverse fringing fields. The clamps were designed using Poisson and Ptrace programs in order to get a magnetic field distribution that allows acceleration for a convenient distance between the magnets. The beam trajectories determined by Ptrace program were confirmed with agreement of 0,1% using the floating wire technique