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Local nanoparticle deposition by AFM
Vaněk, Kamil ; Havlíček, Marek (referee) ; Nováček, Zdeněk (advisor)
This thesis deals with the local deposition of rhodamine 6G and quantum dots solutions using FluidFM hollow probes implemented in the NTegra Prima AFM microscope. The NTegra Prima microscope does not officially support the use of hollow probes, and successful demonstration of the deposition capabilities of implementing hollow probes in this microscope would expand its use. The microscope could thus find applications for unique deposition experiments such as local deposition of perovskite nanocubes for nanophotonic research and others. First, the thesis provides an overview of AFM nanolithography (SPL) techniques. Their parameters, properties and applications are mentioned. In the next section, the use of SPL in the creation of structures for the field of nanophotonics is discussed in more detail. Subsequently, the NTegra Prima microscope and the implementation of hollow probes in this microscope are introduced. In the experimental part, the results of local deposition are presented. The deposition parameters used are mentioned, the procedure for the analysis of the deposited structures is described, and an evaluation of the deposition results is given. Finally, a separate subsection is devoted to the problem of cleaning of hollow probes.
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Preparation and characterization of optical metasurfaces
Weiss, Vlastimil ; Čižmár, Tomáš (referee) ; Dvořák, Petr (advisor)
This thesis presents a comprehensive study on the preparation and characterization of dielectric optical metasurfaces. Optical metasurfaces, which are artificially structured surfaces, enable precise manipulation of electromagnetic waves at a subwavelength scale, surpassing conventional optics in terms of spatial resolution and the complexity of optical transformations. The work is conducted at the Institute of Physical Engineering, Brno University of Technology in colaboration with CEITEC, and involves the use of advanced techniques such as ion beam etching through masks created via electron beam lithography (EBL) and the deposition of optically active materials into EBL matrices. The primary objectives include a thorough literature review, the fabrication of dielectric metasurfaces based on phase control mechanisms, and the detailed morphological and optical characterization of the produced structures. The research employs digital holographic microscopy and confocal optical spectroscopy for optical characterization, as well as numerical and semi-analytical simulations. The results contribute to the ongoing development of high-efficiency optical components and highlight the potential applications of biophotonic devices in the field of nano-optics.
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Semianalytical approach to simulations in nanophotonics
Hrtoň, Martin ; Hohenester, Ulrich (referee) ; Aizpurua, Javier (referee) ; Šikola, Tomáš (advisor)
Numerické simulace se staly nedílnou součástí procesu navrhování v nanofotonice, což nevyhnutelně vedlo k vývoji softwaru specializovaného pro tento úkol. Ačkoli je zde celá řada komerčně dostupných produktů, mnohé aplikace vyžadují datovou analýzu, která překračuje standardní výbavu těchto nástrojů. Zpracování výsledků simulací je těžištěm této práce, kdy důraz je kladen zejména na vývoj semianalytických modelů ušitých na míru jednotlivým experimentům. Spolu s lepší shodou mezi teorií a měřeními tyto modely poskytují také cenný vhled do studovaných fyzikálních procesů. Hlavní část této práce je věnována plazmonicky zesílené elektronové paramagnetické rezonanci (PE EPR), nové metodě využívající kovové antény pro zesílení interakce mezi zářením a materiály s magnetickými přechody mezi spinovými stavy. Jsou zde objasněny základní principy řídící tento jev a představen model umožňující rychlou optimalizaci polí antén pro PE EPR spektroskopii tenkých vrstev. Zvláštní pozornost je pak věnována roli indukovaného proudu a možnostem, které nabízí při projekcích do dalekého pole nebo počítání elektromagnetické interakce mezi objekty. Toto je dále demonstrováno na několika aplikacích, jmenovitě fázovém zobrazování metapovrchů pomocí koherencí řízeného holografického mikroskopu, designu optického prvku pro generování pole svazků na bázi metapovrchu a multipólové analýze elektromagnetických vln emitovaných objekty nacházejícími se uvnitř multivrstvy.
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Modelling electron energy-loss spectra of vanadium dioxide nanostructures
Kabát, Jiří ; Křápek, Vlastimil (referee) ; Konečná, Andrea (advisor)
This thesis concerns the characterization of optical modes in vanadium dioxide (VO2) nanostructures, mainly by simulating numerically electron energy loss spectroscopy (EELS) intensity. Among the studied optical modes, there are plasmons, phonons and Mie-type resonances, for which we performed a literature review. VO2 undergoes a phase transition when reaching a temperature of about 67 °C from the insulating phase to the metallic phase. This phase transition is connected to significant changes in optical properties, which offer potential uses in nanophotonics. The main part of the thesis is devoted to numerical simulations, which were firstly performed for thin VO2 slabs and then for VO2 nanoparticles. In simulations of VO2 nanoparticles in the metallic phase, we observed electron energy losses caused by plasmons and localized surface plasmons, which were then characterized and imaged by spacedependent EELS maps. In nanoparticles in the insulating phase, losses caused by phonon excitations and material absorption were observed. A new kind of loss contribution was observed for some geometries, potentially related to the Mie-type resonances.
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Measurement of resonant properties of plasmonic nanostructures in transmission and reflection mode of far-field spectroscopy
Klement, Robert ; Brzobohatý, Oto (referee) ; Šikola, Tomáš (advisor)
Far-field optical spectroscopy allows for measurement of plasmonic resonances on metallic nanostructures of various shapes and sizes when illuminated by continuous light. Employing dark-field microscopy makes it possible to measure scattering on a localised plasmon excited on a single, isolated nanostructure. For the purpose of these measurements an apparatus based on commercial dual microscope system Nanonics has been put together. Experiments carried out during work on this thesis have shown a great sensitivity of the apparatus in its present form, allowing to measure a plasmonic resonance of a single nanoparticle. Proposed improvements of the apparatus should lead to even greater sensitivity and precision of measurements in the near future.
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Outcoupling of 2D material photoluminescence into nanowire waveguides
Królikowski, David ; Nebojsa, Alois (referee) ; Ligmajer, Filip (advisor)
Modern electronic devices that utilize information about the position of particles in a band structure instead of their electric charge for information transmission have been a subject of rising popularity. One of these devices is represented by an interface that combines transition metal dichalcogenides (TMDC) monolayers with waveguides, aiming to achieve directional coupling of electromagnetic waves. Current efforts to enhance the directionality efficiency are necessary steps towards practical implementation. This diploma thesis focuses on the fabrication and characterization of a new, more efficient model of the described device.
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Modelling electron energy-loss spectra of vanadium dioxide nanostructures
Kabát, Jiří ; Křápek, Vlastimil (referee) ; Konečná, Andrea (advisor)
This thesis concerns the characterization of optical modes in vanadium dioxide (VO2) nanostructures, mainly by simulating numerically electron energy loss spectroscopy (EELS) intensity. Among the studied optical modes, there are plasmons, phonons and Mie-type resonances, for which we performed a literature review. VO2 undergoes a phase transition when reaching a temperature of about 67 °C from the insulating phase to the metallic phase. This phase transition is connected to significant changes in optical properties, which offer potential uses in nanophotonics. The main part of the thesis is devoted to numerical simulations, which were firstly performed for thin VO2 slabs and then for VO2 nanoparticles. In simulations of VO2 nanoparticles in the metallic phase, we observed electron energy losses caused by plasmons and localized surface plasmons, which were then characterized and imaged by spacedependent EELS maps. In nanoparticles in the insulating phase, losses caused by phonon excitations and material absorption were observed. A new kind of loss contribution was observed for some geometries, potentially related to the Mie-type resonances.
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Semianalytical approach to simulations in nanophotonics
Hrtoň, Martin ; Hohenester, Ulrich (referee) ; Aizpurua, Javier (referee) ; Šikola, Tomáš (advisor)
Numerické simulace se staly nedílnou součástí procesu navrhování v nanofotonice, což nevyhnutelně vedlo k vývoji softwaru specializovaného pro tento úkol. Ačkoli je zde celá řada komerčně dostupných produktů, mnohé aplikace vyžadují datovou analýzu, která překračuje standardní výbavu těchto nástrojů. Zpracování výsledků simulací je těžištěm této práce, kdy důraz je kladen zejména na vývoj semianalytických modelů ušitých na míru jednotlivým experimentům. Spolu s lepší shodou mezi teorií a měřeními tyto modely poskytují také cenný vhled do studovaných fyzikálních procesů. Hlavní část této práce je věnována plazmonicky zesílené elektronové paramagnetické rezonanci (PE EPR), nové metodě využívající kovové antény pro zesílení interakce mezi zářením a materiály s magnetickými přechody mezi spinovými stavy. Jsou zde objasněny základní principy řídící tento jev a představen model umožňující rychlou optimalizaci polí antén pro PE EPR spektroskopii tenkých vrstev. Zvláštní pozornost je pak věnována roli indukovaného proudu a možnostem, které nabízí při projekcích do dalekého pole nebo počítání elektromagnetické interakce mezi objekty. Toto je dále demonstrováno na několika aplikacích, jmenovitě fázovém zobrazování metapovrchů pomocí koherencí řízeného holografického mikroskopu, designu optického prvku pro generování pole svazků na bázi metapovrchu a multipólové analýze elektromagnetických vln emitovaných objekty nacházejícími se uvnitř multivrstvy.
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Measurement of resonant properties of plasmonic nanostructures in transmission and reflection mode of far-field spectroscopy
Klement, Robert ; Brzobohatý, Oto (referee) ; Šikola, Tomáš (advisor)
Far-field optical spectroscopy allows for measurement of plasmonic resonances on metallic nanostructures of various shapes and sizes when illuminated by continuous light. Employing dark-field microscopy makes it possible to measure scattering on a localised plasmon excited on a single, isolated nanostructure. For the purpose of these measurements an apparatus based on commercial dual microscope system Nanonics has been put together. Experiments carried out during work on this thesis have shown a great sensitivity of the apparatus in its present form, allowing to measure a plasmonic resonance of a single nanoparticle. Proposed improvements of the apparatus should lead to even greater sensitivity and precision of measurements in the near future.
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