Digital Holography And Optical Metrology
Lecturer: prof. Elena Stoykova, DSc
E-mail: estoykova@iomt.bas.bg
Hours: 30 teaching hours
Annotation:
Digital holography, which records interference pattern of a reference beam with a light beam, reflected from an object, and reconstructs the holographic image by means of computer, finds wide application due to recent advances in laser sources, 2D photosensors, (CCD or CMOS cameras) and digital signal processing. Optical and digital holographic methods are an effective tool for precise remote registration of data about the relief, mechanical and physical properties of macro and micro-objects as well as for 3D visualization of objects.
PhD students get accustomed with the principles of Fourier optics, reconstruction algorithms of digital holograms (Fresnel approach, convolution approach and phase-shifting algorithm). Main approaches for computer generation of holograms are also considered. Holographic interferometry, digital holographic microscopy and visualization of phase objects are also included. Lectures include the theory of speckle phenomena in optics and implementation of speckle-interferometric methods. The main algorithms in optical metrology for processing of fringe patterns as phase-stepping method, Fourier analysis, wavelet techmique, minimization of cost-function are discussed. One of the main advantages of this lecture course is the possibility for MatLab programming for composing codes for digital reconstruction of holograms and processing of real images.
Materials for optical data storage: disposable, reversible and new organic/inorganic composites
Assoc. Prof. Dimana Nazarova, PhD
E-mail: dimana@iomt.bas.bg
Hours: 30 teaching hours
Annotation:
The course studies the most commonly used in recent years, light sensitive media for holographic recording. The basic requirements for these materials are presented, which are important to ensure full transfer of the fine interference picture. The basic characteristics, mechanisms for the image formation, specific treatment processes and methods of storage are also studied. This lecture course also introduces recent trends of research for the development and application of new composite materials, consisting mainly of photopolymer matrices as well as some anisotropic materials containing nanoparticles with different forms, consistence and structures.
Optical properties of organic / inorganic hybrid materials and structures
Prof. Tsvetanka Babeva, PhD
E-mail: babeva@iomt.bas.bg
Hours: 30 teaching hours
Annotation:
The course is suitable for young scientists, specialists and PhD students - physicists and chemists. The knowledge in optics is not obligatory. The aim of the course is students to gain knowledge of the foundation of thin film optics and methods for optical modeling of homogenous and heterogeneous media. The program consists of Maxwell equations for linear medium, refraction and reflection laws, Snell’s law, Fresnel’s equations, transmission and reflection coefficients of thin film and film/substrate, transfer matrix approach, multilayers systems. The widely accepted effective medium theories of Maxwell-Garnett, Lorentz-Lorenz and Bruggeman used for modeling of the optical behavior of hybrid structures are also considered. The emphasis is laid on the advantages and disadvantages of different theories and their applications. Some examples of advanced applications of hybrid structures in photonics is discussed.
Polarization holography and applications: holographic data storage in anisotropic materials
Assoc. Prof. Lian Nedelchev, PhD
E-mail: lian@iomt.bas.bg
Hours: 30 teaching hours
Annotation:
This lecture course gradually introduces the audience to the history and main concept of holography, the terminology used in the field and the general requirements for making a hologram. Some of the most interesting features of the holograms are presented – the parallax effect and the ability to reproduce the entire image of an object even from a small piece of the hologram. Different applications of holography are discussed and the focus is placed on holographic data storage – a technology of the future, offering more than 300 GB of capacity on a CD-sized disc.
Polarization holography allows to register not only the intensity and phase of light, but also its state of polarization i.e. to record the entire information carried by the light field. This is possible only in certain type of materials called photoanisotropic materials. The most effective and therefore most commonly used class of these materials are described – the azopolymers – which have been intensively investigated during the last decades. The applications of azopolymers include recording of optical elements with unique properties, formation of chiral structures that can be used for all-optical switching as well as polarization multiplexing. >Stilbene materials enable polarization recording in the UV and hence allow to increase even further the density and capacity on polarization holographic data storage.
The key advantage of this course is that it presents a modern field of research with very high publication activity in easy to understand way.
Electron microscopy and electron diffraction as a tool for structure and phase composition analysis of materials
Daniela Karashanova, PhD, Associate Professor
E-mail: dkarashanova@yahoo.com
Hours: 30 teaching hours + 15 hours practice
Annotation:
The lecture course is adressed to PhD students in speciality 01.05.05 Physical Chemistry with background in theory of matter structure, geometrical and wave optics.
The essentiality of this course are transmission (TEM) and scanning (SEM) electron mycroscopy, electron crystallography and some analytical methods for chemical composition, related with the electron microscopy, as well as the existing different techniques for sample preparation. Naturally, the course starts with an introduction, concerning the matter's structure theory, fundamentals of crystallography and crystal chemistry, electron – matter interraction. In the main parts, after a hystorical review of the prerequisites for transmission and scanning electron microscopes elaboration, their set-up and working methods are presented in details. The different microscopes' modes, additional devices and their functions are discussed. The main phenomena and processes, related with the image and diffraction patterns formation and registration are presented. In conclusion, some examples, demonstarting the relation of the electron microscopy and analytical methods, with the contemporary trends of the science and technologies, as synthesis of new materials, nanotechnology, nanoelectronics and new energy sources, are done. An attention to the created computer programmes for imaging and TEM analysis results treatement is paid.
A practical course will be held, also. It aims to acquaint the participants with the sample preparation techniques for TEM and SEM, with the procedures of instruments manipulation (starting, stopping and allignement), as well as to work in different modes of the microscopes and to analyse the obtained results.
Fundamentals of Photonics
Prof. DSci. Vera Marinova
E-mail: vmarinova@iomt.bas.bg
Hours: 30 teaching hours
Annotation:
This course covers the basic principles of electromagnetic optics and interaction of the light with matter. Sub-topics will focused on a brief introduction of monochromatic waves (interference and diffraction of light), electromagnetic optics (electromagnetic waves, absorption and dispersion of light; slow and fast light in resonant media, optics in magnetic and metamaterials); polarization optics (reflection and refraction of light, evanescent waves, dispersion); optics of anisotropic media (crystal optics, optics of liquid crystals, polarization devices); semiconductor optics (interaction of photons with charge carriers, semiconductor photon sources and devices); principles of electro-optics (electro-optics of anisotropic media, photorefractivity) and non-linear optics (anisotropic and dispersive non-linear media). The purpose of fundamentals of photonics teaching is to introduce some of current issues of modern technology for development of advanced multifunctional materials (including graphene and 2D materials) and device fabrication that take place in the subwavelength (nanometer) scales.
Introduction to new materials
Dessislava Kostadinova, PhD, аssist. Professor
Hours: 20 teaching hours
Annotation:
The aim of the course is to introduce PhD students to the field of new materials. The course includes a brief history of the use and creation of materials, the scientific methods, methods of preparation of advanced materials, and briefly discusses the techniques of analysis and their application areas. The course shows examples of scientific publications and video materials, as well as cited prestigious awards and patents related to the field of new materials. Particular attention is paid to the functionalized materials and their methods of preparation.