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Application of metamaterial structures in terahertz spectral range
Šibík, Juraj ; Kužel, Petr (advisor) ; Čtyroký, Jiří (referee)
The thesis is devoted to a research on metamaterials for terahertz spectral range based on deeply etched silicon. The aim of the work is a theoretical conception and experimental realization of wave plates for selected terahertz frequencies. These wave plates are made of silicon substrates with an etched two-dimensional periodic microstructure where the dimensions of an elementary cell are below the considered wavelength. Theoretical proposal is optimized using the transfer matrix formalism. We designed and experimentally characterized quarter-wave plates for frequencies 0.5 THz and 1 THz and a half-wave plate for frequency 1 THz.
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Time-Resolved Terahertz Spectroscopy Applied to the Investigation of Magnetic Materials and Photonic Structures
Němec, Hynek ; Kužel, Petr (advisor) ; Čtyroký, Jiří (referee) ; Crozat, Paul (referee)
Two distinct branches of optics are combined in this work: Time-domain terahertz spectroscopy, and photonic structures. The work at rst provides a survey of tools utilized for exploration of the terahertz region, and it enriches them by a method for simultaneous determination of dielectric and magnetic response of materials and metamaterials. Photonic structures operating in the terahertz range form the subject of the rest of this thesis. A periodically modulated dielectric waveguide is studied theoretically using a modal method: The band structure of guided and leaky modes is calculated and resonant modes are described. One-dimensional photonic crystals with a defect are then investigated in detail. Formation of defect modes is analyzed theoretically in a photonic crystal with a twinning defect. The analysis makes it possible to formulate requirements on a design of a structure with defect modes tunable by external parameters. Following these guidelines, we have successfully designed, fabricated and characterized photonic crystals with thermally tunable defect modes with relative tunability reaching 60 %.
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Two-dimensional modelling of photonic structures
Čtyroký, Jiří
A novel method for two-dimensional modelling of integrated photonic structures by using of harmonic expansion of optical fields is presented. The principle of the method and its recent improvements are described. The method is critically assessed and compared with other modal methods, namely with the bi-directional eigenmode expansion method and with the Fourier expansion method. A few examples if its application are shown, too.
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Editorial
Čtyroký, Jiří
In introductory page of the Proceedings from 11th European Conference on Integrated Optics ECIO'03 draws readers attention to the history of beginnings of this series of conferences, their aim and proffesional orientation. A rigorous selection procedure of contributed papers is briefly mentioned and their distribution into session commented. The 11th International Workshop on the Optical Waveguide Theory and Numerical Modelling organised jointly with the ECIO'03 conference is noticed too.
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