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Electrotransport properties of CuMnAs single crystals
Volný, Jiří ; Uhlířová, Klára (advisor)
Electrical transport measurement of small, irregular shape sample is difficult task. In order to overcome these limitations, this thesis employed a focused ion beam microfabrication. Process of microfabrication is successfully tested on a room temperature antiferromagnet CuMnAs. Temperature dependence resistivity and magnetoresistance of tetragonal bulk CuMnAs single crystal is found to be strongly anisotropic due to layered structure and magnetic order. Anisotropic magnetoresistance shows two fold symmetry and reached a magnitude of 0.12 %. Employing the∼ phenomenological Stoner-Wohlfarth we conclude that the sample has uniaxial magnetic anisotropy with an easy axis not pointing along any principal crystallographic direction and behaves like a two domain antiferromagnet.
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Electrotransport properties of CuMnAs single crystals
Volný, Jiří ; Uhlířová, Klára (advisor) ; Zázvorka, Jakub (referee)
Electrical transport measurement of small, irregular shape sample is difficult task. In order to overcome these limitations, this thesis employed a focused ion beam microfabrication. Process of microfabrication is successfully tested on a room temperature antiferromagnet CuMnAs. Temperature dependence resistivity and magnetoresistance of tetragonal bulk CuMnAs single crystal is found to be strongly anisotropic due to layered structure and magnetic order. Anisotropic magnetoresistance shows two fold symmetry and reached a magnitude of 0.12 %. Employing the∼ phenomenological Stoner-Wohlfarth we conclude that the sample has uniaxial magnetic anisotropy with an easy axis not pointing along any principal crystallographic direction and behaves like a two domain antiferromagnet.
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Microstructures fabrication for transport properties measurements of heavy fermion compounds
Volný, Jiří ; Uhlířová, Klára (advisor) ; Prchal, Jiří (referee)
In this thesis, we focus on preparation of micro-devices for resistivity measure- ment of CeCoIn5 using focused ion beam technique. Single crystal samples of ∼ 50 µm length were carved out by focused ion beam and transported on silicon sub- strates with prepared gold structures for electrical resistivity measurement. The samples were conductivily attached to gold contact pads by focused ion beam in- duced platinum deposition. Several steps and techniques were optimized: electron litography, golden pads electrical resitivity measurement and platinum structures electrical resitivity measurement and microstructure transport. Electrical resisti- vity measurement of CeCoIn5 single crystal showed superconductive transition at Tc = 2.27 K and H-T phase diagram was created from measurement in magnetic fields. The result obtained from bulk sample are in agreement with literature. On the other hand measurement of micro-devices showed no superconducting transition, suggesting unsufficient quality of samples. 1
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Management kvality ve veřejné správě - Model CAF
Volný, Jiří ; Mates, Pavel (advisor) ; Janoušková, Alena (referee)
Práce se snaží reagovat na posun ve vnímání fungování veřejné správy. Tím je zejména přechod od nařizovací správy k chápání správy jako službě veřejnosti. Jednou z možností modernizace a zlepšení práce veřejné správy je aplikace metod managementu kvality. V práci se poukazuje na rozdílnost veřejné správy a celého veřejného sektoru oproti soukromému. Ze soukromé sféry jsou zdůrazněny metody, které mohou být aplikovatelné i ve veřejné správě. Větší část práce je pak věnována Modelu CAF (Common Assessment Framework), který byl speciálně navržen pro implementaci ve veřejném sektoru. Pro jeho snazší zavedení jsou uvedeny i upravené praktické příklady ze starších projektů.
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