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Study of Properties of Surface Plasmon Polariton by Using Scanning Near-Field Optical Microscopy
Neuman, Tomáš ; Kalousek, Radek (referee) ; Dvořák, Petr (advisor)
This bachelor`s thesis deals with the study of properties of surface plasmon polaritons (SPPs) propagating along the metal - dielectric interface. The interference of SPPs was experimentally examined by a scanning near-field optical microscope (SNOM) on plasmonic structures prepared by focused ion beam (FIB) etching. Interference patterns caused by SPPs propagating from prepared excitation slits were observed. Detected interference patterns were theoretically discussed. Finally, the sensitivity of the SPP coupling on the polarization of the excitation laser beam was experimentally confirmed.
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Rigorous Simulation of Light Interaction with Cells
Dršata, Martin ; Kalousek, Radek (referee) ; Petráček, Jiří (advisor)
This bachelor thesis focuses on rigorous simulations of light scattering by living cells. The first part is dedicated to brief introduction to the given issues and the basic description of the often used computational methods and models of cell structures. Experimental part deals with light scattering simulations using the finite difference time domain method (FDTD). Models of spherical cell and red blood cell are used in these simulations. The aim of the calculations for the first model is to assess the accuracy of the FDTD method with respect to the analytical method using Mie theory of light scattering.
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Physics of Metamaterials
Láska, Martin ; Kalousek, Radek (referee) ; Dub, Petr (advisor)
The bachelor work deals with electrodynamics of metamaterials for which both the electric permittivity and magnetic permeability are simultaneously negative. It is shown that the double negative media are described by a negative refraction index which has an important impact on optics laws. In particular, the negative refraction is demonstrated by simulation of interaction of the Gauss monochromatic beam impinging on a negative refractive material. Next, the electromagnetic energy propagation in the negative refractive materials is studied. It is shown that the energy propagation velocity equals the group velocity, which has the opposite sign than the phase velocity. Finally, Fresnel formulas valid both for positive and negative refraction index are given.
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Excitation and detection of plasmon polaritons
Brtek, Tomáš ; Kalousek, Radek (referee) ; Tomanec, Ondřej (advisor)
Behavior of surface plasmon polaritons and localized surface plasmons is strongly dependent on parametres of metalic surfaces and on parametres of structures created on the surfaces. This work deals with plasmonics mainly in the field of producing structures for plasmonics resonant systems, which might be suitable for excitation of surface plasmons by modified scanning tunneling microscopy. Final structures made for this purpose were described. Techniques for the excitation of plasmons are presented.
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Modelling of photonic structures using Finite-difference time-domain method
Procházka, Pavel ; Kalousek, Radek (referee) ; Petráček, Jiří (advisor)
This bachelor thesis is focused on the basic description of the finite-difference time-domain method (FDTD) which serves to the numerical solution of Maxwell's equations. FDTD is very used today because during one calculation it is possible to obtain results in wide frequency spectrum. The thesis contains deduction of \mbox{equations} for description of this method and algorithm of calculation. The main goals of this thesis are the identification of the free Meep software, which is constructed for this calculations, and understanding of its properties. Most of Meep functions are described on three examples in the second part of bachelor thesis.
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Excitation and Detection of Plasmon Polaritons
Šustr, Libor ; Schmidt, Eduard (referee) ; Kalousek, Radek (advisor)
The diploma thesis is aimed to excitation and detection of surface plasmon polaritons by visible light. First of all, we will briefly remind some basic principles like waves, electromagnetic wave, light on the interface and optical properties of metals. By using these principles we show presence of surface plasmon polaritons states. After the explanation of their properties there will be clearly visible reasons for aplications of the special excitationand detection methods. We will describe especially the prism coupling, periodic grating coupling and SNOM. Two last sections deal with computer simulations and experiments related to these methods. This means we can exemplify some knowledge presented in previous chapters. Results of simulations are compared with the experiment where we study the excitations of surface plasmon polaritons by periodic grating on aluminium surface.
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SNOM probes with special properties
Slabý, Vít ; Kalousek, Radek (referee) ; Spousta, Jiří (advisor)
This bachelor thesis deals with scanning near-field optical microscopy. With SNOM we examined experimentally the near field of the interference of surface plasmon polaritons (PPP) on plasmonic structures consisting of slits in a metal layer a we discuss the effect of probe characteristics on the measurement results.Effect of few characteristics is simulated numerically. Findings obtained in the previous experiments are used for the construction designing of an experimental device called NanoGIS, which should serve for the nanostructure manufacturing.
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Study of Optical Properties of Metallic Structures and Their Applications in Nano-Optics
Neuman, Tomáš ; Munzar,, Dominik (referee) ; Kalousek, Radek (advisor)
Interaction of metallic structures with electromagnetic radiation is a living topic of near-field optics including plasmonics and nanophotonics. The field-matter interaction treated on the subwavelength scale opens the path to a wide range of applications, among others to different variants of the surface enhanced spectroscopy. In this thesis we theoretically describe how the near-field properties of the metallic structures can be accessed by a probe of near-field scanning optical microscope. Formation of the signal in the near-field microscopy utilizing weakly interacting probes is discussed. Further, we elucidate the mechanism of the surface enhanced infrared spectroscopy. We utilize a model example of linear dipole antennas interacting with sample structures. A close connection is found between the spectroscopic signal and signal of the scattering type near-field optical microscopy.
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Development of UHV STM/AFM
Pavelec, Jiří ; Neuman, Jan (referee) ; Kalousek, Radek (advisor)
The main focus of the thesis is on the actuator, which is used for nanopositioning of laser beam in-site AFM (Atomic Force Microscopy). The appropriate shape of supply pulse and frequencies were searched and optimized. They make slip-stick motion of the piezo actuator. Possibilities of solving troubles with UHV (Ultra High Vacuum) are described on the basis of experiment and simulation.
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