Artificial reflecting structures based on metamaterials
Tcvetkova, Svetlana (2015)
Diplomityö
2015
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi-fe201505218698
https://urn.fi/URN:NBN:fi-fe201505218698
Tiivistelmä
This thesis studies metamaterial-inspired mirrors which provide the most general control
over the amplitude and phase of the reflected wavefront. The goal is to explore practical
possibilities in designing fully reflective electromagnetic structures with full control over
reflection phase. The first part of the thesis describes a planar focusing metamirror with
the focal distance less than the operating wavelength. Its practical applicability from the
viewpoint of aberrations when the incident angle deviates from the normal one is verified
numerically and experimentally. The results indicate that the proposed focusing metamirror can be efficiently employed in many different applications due to its advantages over other conventional mirrors. In the second part of the thesis a new theoretical concept of reflecting metasurface operation is introduced based on Huygens’ principle. This concept in contrast to known approaches takes into account all the requirements of perfect metamirror operation. The theory shows a route to improve the previously proposed metamirrors through tilting the individual inclusions of the structure at a chosen angle from normal. It is numerically tested and the results demonstrate improvements over the previous design.
over the amplitude and phase of the reflected wavefront. The goal is to explore practical
possibilities in designing fully reflective electromagnetic structures with full control over
reflection phase. The first part of the thesis describes a planar focusing metamirror with
the focal distance less than the operating wavelength. Its practical applicability from the
viewpoint of aberrations when the incident angle deviates from the normal one is verified
numerically and experimentally. The results indicate that the proposed focusing metamirror can be efficiently employed in many different applications due to its advantages over other conventional mirrors. In the second part of the thesis a new theoretical concept of reflecting metasurface operation is introduced based on Huygens’ principle. This concept in contrast to known approaches takes into account all the requirements of perfect metamirror operation. The theory shows a route to improve the previously proposed metamirrors through tilting the individual inclusions of the structure at a chosen angle from normal. It is numerically tested and the results demonstrate improvements over the previous design.