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Localized oxidation of vanadium films accompanied by in-situ analysis
Spousta, Jiří ; Neuman, Jan (referee) ; Ligmajer, Filip (advisor)
V předložené diplomové práci se zabýváme popisem a aplikací námi vyvinuté metody lokální oxidace vanadových vrstev v komoře elektronového mikroskopu. K tomuto účelu používáme duté optické vlákno, které na zvolené místo na povrchu vzorku může přivést jak pracovní plyn (O\2), tak i intenzivní laserové světlo ($\lambda=532$\,nm). Po několika iteracích hledání nejvhodnější konfigurace lokálního ovlivňování povrchu vanadu (jednovláknová, případně dvouvláknová verze metody) byla jako nejvhodnější vyhodnocena varianta, ve které bylo planární duté optické vlákno (připevněné k ladičce AFM mikroskopu LiteScope od firmy NenoVision) definovaným způsobem přiblíženo k povrchu vanadové vrstvy. Blízkost povrchu a dostatečný tok pracovního plynu kapilárami dutého vlákna vedly k tomu, že se nám vanadovou vrstvu úspěšně podařilo zoxidovat. V práci jsou rovněž popsány výsledky měření Ramanovy spektroskopie takto lokálně ovlivněných vanadových vrstev, které ukázaly, že zvolená metoda, kterou jsme objevili, byla úspěšná a otevírá nové možnosti přípravy tohoto zajímavého materiálu. V práci jsou rovněž uvedeny a popsány nezbytné konstrukční úpravy stávající experimentální sestavy pro lokální oxidaci (multifunkčního systému vstřikování plynu) a popis přípravy tenkých vanadových vrstev metodou IBAD
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Controlling and Evaluation of Laser Micromanipulation Experiments
Kaňka, Jan ; Jákl, Petr (referee) ; Provazník, Ivo (advisor)
This work is focused on the development of a user friendly software interface using the LabViewTM environment that simplifies running of various experiments using laser micromanipulations and laser microspectroscopy of living microorganisms. Both techniques have been developing very fast for the last decade and belong to the growing group of contact-less and nondestructive techniques for manipulation and diagnostics of individual living microorganisms, cells, or viruses. Within this project we mastered the driving of peripheries, calibration of CCD scene, real-time image processing of the CCD scene, automatic selection of the cell for further laser processing, acquisition and processing of the Raman spectrum from living microorganisms. The final goal of our activity is fully automatic laser-based sorter of living cells depending on their chemical compositions. This work has been elaborated at the Institute of Scientific Instruments of the ASCR, v.v.i. under the supervision of prof. Pavel Zemanek.
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Raman assembly for radiation analysis
Stránská, Lenka ; Ježek, Jan (referee) ; Dostál, Zbyněk (advisor)
For Raman spectroscopy is a need to introduce a laser light into an optic fiber and analyze a collected light at the same time. Therefore it was proposed a specialized optical system. This system can also be used to measure other spectroscopy methods such as photoluminescence. In the theoretical part of this theses, was discussed both mentioned methods and their instrumentations. In addition to the Raman spectroscopy, was also shown some special cases of Raman spectroscopy for enhanced measurement of Raman scattering. The problem of weak signal detection and its reading is also discussed in the theoretical part of the thesis. In the practical part of this thesis was discussed the mechanical design of the optical system and the choice of optical elements that are used in the system. Next, is introduced the manufactured system, which design is based on the parameters of the chosen optical elements. The practical part of the thesis ends with an assembly and testing of the proposed system.
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Raman assembly for radiation analysis
Stránská, Lenka ; Ježek, Jan (referee) ; Dostál, Zbyněk (advisor)
For Raman spectroscopy is a need to introduce a laser light into an optic fiber and analyze a collected light at the same time. Therefore it was proposed a specialized optical system. This system can also be used to measure other spectroscopy methods such as photoluminescence. In the theoretical part of this theses, was discussed both mentioned methods and their instrumentations. In addition to the Raman spectroscopy, was also shown some special cases of Raman spectroscopy for enhanced measurement of Raman scattering. The problem of weak signal detection and its reading is also discussed in the theoretical part of the thesis. In the practical part of this thesis was discussed the mechanical design of the optical system and the choice of optical elements that are used in the system. Next, is introduced the manufactured system, which design is based on the parameters of the chosen optical elements. The practical part of the thesis ends with an assembly and testing of the proposed system.
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Spectroscopic Investigation of Lattice Dynamics in Multidomain Ferroelectrics
John Vakkechalil, Elizabeth ; Hlinka, Jiří (advisor) ; Hlídek, Pavel (referee) ; Hehlen, Bernard (referee)
Title: Spectroscopic investigations of lattice dynamics in multidomain ferroelectrics Author: Elizabeth Vakkechalil John Department: Department of Condensed Matter Physics Institution: Department of Dielectrics, Institute of Physics, AVČR, Na Slovance 2, Praha 8, 182 21, Czech Republic. Supervisor: Ing. Jiří Hlinka, PhD., Department of Dielectrics, Institute of Physics, AVČR., Na Slovance 2, Praha 8, 182 21, Czech Republic. Consultants: RNDr. Stanislav Kamba CSc., Ing. Ivan Gregora CSc. Fyzikální ústav AVČR, Na Slovance 2, Praha 8, 182 21, Czech Republic. Abstract: Lead based ferroelectric perovskites exhibit attractive physical and structural properties. Ferroelectric domains are known to have a very essential impact on dielectric and piezoelectric properties of ferroelectrics. Tailoring of domain structures allows to change the macroscopic symmetry of the material and to purposely modify its average tensor properties. Ferroelastic domains play also a key role in physics of epitaxial ferroelectric films. Here we studied signature of domain structure in PbTiO3 thin film grown by metalorganic chemical vapor deposition technique on different substrates, namely LaAlO3, MgO, NdGaO3, SrTiO3 (100), SrTiO3 (110), SrTiO3 (111) doped with 0.5% Nb and LSAT. Certain aspects of domain structure can be...
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Controlling and Evaluation of Laser Micromanipulation Experiments
Kaňka, Jan ; Jákl, Petr (referee) ; Provazník, Ivo (advisor)
This work is focused on the development of a user friendly software interface using the LabViewTM environment that simplifies running of various experiments using laser micromanipulations and laser microspectroscopy of living microorganisms. Both techniques have been developing very fast for the last decade and belong to the growing group of contact-less and nondestructive techniques for manipulation and diagnostics of individual living microorganisms, cells, or viruses. Within this project we mastered the driving of peripheries, calibration of CCD scene, real-time image processing of the CCD scene, automatic selection of the cell for further laser processing, acquisition and processing of the Raman spectrum from living microorganisms. The final goal of our activity is fully automatic laser-based sorter of living cells depending on their chemical compositions. This work has been elaborated at the Institute of Scientific Instruments of the ASCR, v.v.i. under the supervision of prof. Pavel Zemanek.
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