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Production of electricity from the vibration of the bicycle
Novák, Pavel ; Sobotka, Jiří (referee) ; Koutný, Martin (advisor)
The work is focused on methods of obtaining energy from the environment. In the project, there are summarized and generally described some methods of energy conversion. A more detailed description is aimed at a method on the principal of the Faraday's effect. The work involves a calculation of the electromagnetic generator with specific parameters, a simulation of the calculated generator and builds a real product on the basis of the previous theoretical calculation. The aim is to create a product that accumulates the energy obtained in the attached battery.
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The suppresion of mechanical stress impacts in fiber optic transmission systems
Pavlů, Michal ; Szabó, Zoltán (referee) ; Drexler, Petr (advisor)
This bachelors project deals with the suppresion of mechanical stress impacts in fiber optic transmission systems. Factors that have major influence on the polarization state distortion in optical fiber are discussed. It has been propřed the utilization of orthoconjugate retroreflector (OKR) for the compensation of polarization state degeneration. The theoretical analysis of this method is performed. The OKR method has been experimentally verified in the fiber optic current sensor. On the basis of results which were obtained by experimental verification the experimental results show evidence konvenience of the designed method.
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Spectroscopic studies of new generation of optical and magneto-optical materials
Butková, Eva ; Veis, Martin (advisor) ; Chlan, Vojtěch (referee) ; Zemen, Jan (referee)
Title: Spectroscopic studies of new generation of optical and magneto-optical materials Author: Eva Butková Department / Institute: Institute of Physics of Charles University. Department of Materials Science and Technology of Nagaoka University of Technology. Supervisors of the doctoral thesis: RNDr. Martin Veis, Ph.D., Division of Magneto-optics, Institute of Physics of Charles University Dr. Takayuki Ishibashi, Ph.D., Department of Materials Science and Technology, Nagaoka University of Technology Abstract: In recent years, novel optical and magneto-optical devices have been proposed. This ranges from integrated photonic devices such as 3D holographic displays to magnetic recording, non- reciprocal photonic devices such as optical isolators and circulators or high-energy X-ray/gamma ray detectors. These devices, however, require suitable materials with tunable optical and magneto-optical properties. Presented thesis aims to systematically study such materials, namely GdxFe(100-x), magnetic garnets (Y3-xBixFe5O12, Nd2BiFe(5-x)GaxO12, Nd0.5Bi2.5Fe(5-x)GaxO12) and Ce(0.95-x)HfxCo0.05O(2-δ). Systematic study is carried out by the combination of experimental methods of spectroscopic ellipsometry, magneto-optical Kerr effect spectroscopy and Faraday effect spectroscopy. Experimental data are confronted to...
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Studium fyzikálních vlastostí magnetických oxidů spektroskopickými metodami
Zahradník, Martin ; Veis, Martin (advisor) ; Kouřil, Karel (referee)
Two groups of magnetic oxides were investigated in this thesis. Thin films of La2/3Sr1/3MnO3 (LSMO) deposited by pulsed laser deposition (PLD) on SrTiO3 (STO) substrates were characterized by polar and longitudinal magneto-optical (MO) Kerr spectroscopy. Experimental results were compared to theoretical calculations based on the transfer matrix formalism. A very good agreement between experimental and theoretical data revealed high magnetic ordering down to 5 nm of film thickness as well as a mechanism of suppression of double exchange interaction near the LSMO/STO interface. Magnetically doped Ce1-xCoxO2-δ films deposited by PLD on MgO (x = 0.05 and 0.10) and oxidized Si (x = 0.20) substrates were studied by combination of spectroscopic ellipsometry and MO Faraday and Kerr spectroscopy. Both diagonal and off-diagonal permittivity tensor components were obtained and verified by theoretical calculations confronted with experimental data. Diagonal spectra revealed two optical transitions from oxygen to cerium states. Off-diagonal spectra revealed two paramagnetic transitions involving cobalt ions. An essential influence of cobalt doping on the resulting ferromagnetic properties of CeO2 was observed.
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Studium fyzikálních vlastností magnetických oxidů spektroskopickými metodami
Zahradník, Martin ; Veis, Martin (advisor)
Two groups of magnetic oxides were investigated in this thesis. Thin films of La2/3Sr1/3MnO3 (LSMO) deposited by pulsed laser deposition (PLD) on SrTiO3 (STO) substrates were characterized by polar and longitudinal magneto-optical (MO) Kerr spectroscopy. Experimental results were compared to theoretical calculations based on the transfer matrix formalism. A very good agreement between experimental and theoretical data revealed high magnetic ordering down to 5 nm of film thickness as well as a mechanism of suppression of double exchange interaction near the LSMO/STO interface. Magnetically doped Ce1-xCoxO2-δ films deposited by PLD on MgO (x = 0.05 and 0.10) and oxidized Si (x = 0.20) substrates were studied by combination of spectroscopic ellipsometry and MO Faraday and Kerr spectroscopy. Both diagonal and off-diagonal permittivity tensor components were obtained and verified by theoretical calculations confronted with experimental data. Diagonal spectra revealed two optical transitions from oxygen to cerium states. Off-diagonal spectra revealed two paramagnetic transitions involving cobalt ions. An essential influence of cobalt doping on the resulting ferromagnetic properties of CeO2 was observed.
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Compact Fiber-Optic Current Sensor Utilizing Multiple Modes
Skalský, Michal
In this paper, a simple and compact fiber-optic current sensor utilizing a standard telecom fiber is demonstrated. The sensor employs a Faraday effect introducing a circular birefringence, which is added to a birefringence induced by fiber coiling. The experiments revealed that multi-mode propagation of light with wavelength of 633 nm may exhibited much better sensitivity to the Faraday effect and is less harmed by the parasitic birefringence compared to single-mode beam with 1550 nm.
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Studium fyzikálních vlastností magnetických oxidů spektroskopickými metodami
Zahradník, Martin ; Veis, Martin (advisor)
Two groups of magnetic oxides were investigated in this thesis. Thin films of La2/3Sr1/3MnO3 (LSMO) deposited by pulsed laser deposition (PLD) on SrTiO3 (STO) substrates were characterized by polar and longitudinal magneto-optical (MO) Kerr spectroscopy. Experimental results were compared to theoretical calculations based on the transfer matrix formalism. A very good agreement between experimental and theoretical data revealed high magnetic ordering down to 5 nm of film thickness as well as a mechanism of suppression of double exchange interaction near the LSMO/STO interface. Magnetically doped Ce1-xCoxO2-δ films deposited by PLD on MgO (x = 0.05 and 0.10) and oxidized Si (x = 0.20) substrates were studied by combination of spectroscopic ellipsometry and MO Faraday and Kerr spectroscopy. Both diagonal and off-diagonal permittivity tensor components were obtained and verified by theoretical calculations confronted with experimental data. Diagonal spectra revealed two optical transitions from oxygen to cerium states. Off-diagonal spectra revealed two paramagnetic transitions involving cobalt ions. An essential influence of cobalt doping on the resulting ferromagnetic properties of CeO2 was observed.
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Studium fyzikálních vlastostí magnetických oxidů spektroskopickými metodami
Zahradník, Martin ; Veis, Martin (advisor) ; Kouřil, Karel (referee)
Two groups of magnetic oxides were investigated in this thesis. Thin films of La2/3Sr1/3MnO3 (LSMO) deposited by pulsed laser deposition (PLD) on SrTiO3 (STO) substrates were characterized by polar and longitudinal magneto-optical (MO) Kerr spectroscopy. Experimental results were compared to theoretical calculations based on the transfer matrix formalism. A very good agreement between experimental and theoretical data revealed high magnetic ordering down to 5 nm of film thickness as well as a mechanism of suppression of double exchange interaction near the LSMO/STO interface. Magnetically doped Ce1-xCoxO2-δ films deposited by PLD on MgO (x = 0.05 and 0.10) and oxidized Si (x = 0.20) substrates were studied by combination of spectroscopic ellipsometry and MO Faraday and Kerr spectroscopy. Both diagonal and off-diagonal permittivity tensor components were obtained and verified by theoretical calculations confronted with experimental data. Diagonal spectra revealed two optical transitions from oxygen to cerium states. Off-diagonal spectra revealed two paramagnetic transitions involving cobalt ions. An essential influence of cobalt doping on the resulting ferromagnetic properties of CeO2 was observed.
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Production of electricity from the vibration of the bicycle
Novák, Pavel ; Sobotka, Jiří (referee) ; Koutný, Martin (advisor)
The work is focused on methods of obtaining energy from the environment. In the project, there are summarized and generally described some methods of energy conversion. A more detailed description is aimed at a method on the principal of the Faraday's effect. The work involves a calculation of the electromagnetic generator with specific parameters, a simulation of the calculated generator and builds a real product on the basis of the previous theoretical calculation. The aim is to create a product that accumulates the energy obtained in the attached battery.
|
|
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The suppresion of mechanical stress impacts in fiber optic transmission systems
Pavlů, Michal ; Szabó, Zoltán (referee) ; Drexler, Petr (advisor)
This bachelors project deals with the suppresion of mechanical stress impacts in fiber optic transmission systems. Factors that have major influence on the polarization state distortion in optical fiber are discussed. It has been propřed the utilization of orthoconjugate retroreflector (OKR) for the compensation of polarization state degeneration. The theoretical analysis of this method is performed. The OKR method has been experimentally verified in the fiber optic current sensor. On the basis of results which were obtained by experimental verification the experimental results show evidence konvenience of the designed method.
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