Author: Tatjana Gric
Dissertation title: Electromagnetic field and dispersion characteristic calculations of open waveguides made of absorptive materials
Fields of science: Physical sciences, Physics (02P), Condensed matter: Electronic structure; Electrical, Magnetic and optical properties; Superconductors; Magnetic resonance; Relaxation; Spectroscopy (P260)
Scientific supervisor: Prof. Dr. Habil. Liudmila Nickelson
Defence of the dissertation: 2011-11-25
The object of the research
The object of the research is the waveguide made of absorptive materials.
The aim of the work - to find the peculiarities of the electrodynamical characteristics and to define the areas of their applications in the microwave devices.
The obtained research results can be useful for creating of the microwave electronic devices, for example, filters, modulators, phase shifters, absorbers. The created algorithms are useful in order to investigate the absorptive material waveguides of the complicated cross-shapes.
- The open waveguides on the basis of absorptive materials with different shapes of the cross-section can be investigated using the created computer algorithms. We are able to calculate the dispersion characteristic and 2D and 3D electromagnetic field distributions. These results can be very useful constructing the waveguide device.
- The created computer algorithms were used investigating the waveguides made of the new materials, i. e. metamaterials, SiC. The got results are in good agreement with the well known electrodynamical laws. By this way the created computer software could be used investigating waveguides made of different materials.
- The circular metamaterial waveguides (r = 2 mm, r = 2.5 mm) could be used as filters. However the losses of the first higher mode propagating in the waveguide with the smaller radius change in an irregular manner. By this reason the main mode could be modulated in the smaller waveguides.
- The circular SiC waveguide (r = 2.5 mm) could be used as modulator. The wave phase could be modulated changing the temperature of the waveguide.
- Changing the dimensions of the periodical waveguide, i.e. the dimensions of the air holes and their dimensions, we can reach the suitable electrodynamical characteristics of the waveguide, i.e. the dispersion characteristics and electromagnetic field distributions.
Gric, T.; Nickelson, L. & Asmontas, S. 2010-11-25, Waveguide Modulator. Lietuvos Respublikos patentas Nr. LT 5710. Application of Invention 2010-040 is given in Official bulletin of the state patent bureau of the republic of Lithuania 2010/11, ISSN 1648- 9985.