1,721,134 research outputs found
Studium a využití povrchových plazmonů v terahertzové spektrální oblasti
Get PDFTitle: Study and application of surface plasmons in terahertz spectral range Author: Peter Darebník Department: Department of Chemical Physics and Optics Supervisor: doc. RNDr. Petr Kužel, Dr., department of Chemical Physics and Optics - external employee Abstract: The goal of this thesis is analytical, numerical and experimental study of surface plasmons in terahertz spectral range The description of the surface plasmon propagation along metal/dielectric interface can be done purely analytically. Our goal is to obtain the description of the surface plasmon propagating in more complex dielectric layered structures which are in contact with metallic layer. Analysis of the surface plasmon dispersion curves in anisotropic layered structure was done numerically. Existing transmission terahertz spectroscopy experiment was expanded by an arrangement that allows us to excite the surface plasmon on the metallic layer and allows us to measure its characteristics after the transmission of samples, that are in contact with this layer. Obtained theoretical and experimental data were then evaluated, so we could conclude to which extent can the surface plasmon be used for spectroscopic purposes in terahertz range. We concluded, that we were able to describe surface plasmons in layered structures including anisotropic..
Rare-earth doped and undoped solid-state materials for photonic applications
No full textTitle: Rare-earth doped and undoped solid-state materials for photonic applica- tions Author: Jan Hrabovský Department: Institute of Physics of Charles University Supervisor: RNDr. Martin Veis, PhD., Institute of Physics of Charles University Abstract: The present doctoral thesis investigates the structural, optical, and magneto-optical properties of undoped and rare-earth doped solid-state materials for photonic applications, focusing on both amorphous and crystalline systems. Tellurite glasses, as representatives of amorphous materials, are investigated as potential hosts for donation of rare-earth ions, particularly in multicomponent TeO2-ZnO-BaO and TeO2-BaO-Bi2O3 glass systems. These glasses are stud- ied for their wide glass-forming ability, thermal stability, optical transparency from ultraviolet to mid-infrared, and promising optical and magneto-optical properties, which makes them suitable for optical fibers, lasers, and amplifiers. Fiber-drawing and rare-earth doping are demonstrated, alongside new methods for long-wavelength/phonon edge evaluation in non-crystalline solids. Obtained results are then compared to pure TeO2 glass, which optical and magneto-optical spectral characteristics are presented in a wide spectral range from ultraviolet to far-infrared. Moreover, linear refractive index and..
Magnetic nanostructures for recording and optical sensors
No full textTitle: Magnetic nanostructures for recording and optical sensors Author: Eva Lišková Department: Institute of Physics, Charles University Supervisor: Prof. Ing. Štefan Višňovský, DrSc. Abstract: Magneto-optical (MO) spectra of multilayered structures with enhanced MO effect were studied using the polar and longitudinal Kerr spectroscopy with oblique angle of light incidence in the photon energy range 1.2 eV to 5 eV. The samples with Fabry- Perot cavity like architecture, were modeled using Yeh matrix formalism. Two sets of samples, with composition FeF2/Fe/FeF2 and AlN/Fe/AlN, were prepared by molecular beam epitaxy and sputtering. The relations were studied between the position of the enhanced peak in the MO spectra and the structure. Second part of this work was devoted to the Pt/Co/Pt structures and the influence of the ion implantation on MO spectra and structural composition. The studied multilayer structures present interest for MO sensor and memory applications. Keywords: Magneto-optical Kerr effect, Magneto-optical sensor, Fabry-Perot resonator, Ion implantatio
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