Enhanced transmission via epsilon-near-zero metamateria
Ghasemzadeh, Farhad (2020)
2020
Degree Programme in Science and Engineering, MSc (Tech)
Tekniikan ja luonnontieteiden tiedekunta - Faculty of Engineering and Natural Sciences
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Hyväksymispäivämäärä
2020-05-10
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:tuni-202005085077
https://urn.fi/URN:NBN:fi:tuni-202005085077
Tiivistelmä
Epsilon-Near-Zero (ENZ) metamaterials, including both natural and fabricated, has been a hot topic of studies in recent twenty years. Theoretical background for ENZ metamaterials and their properties such as phase conservation or static behavior of the propagating dynamic electromagnetic field are investigated thoroughly. Functional capabilities such as uses in phase front engineering, subwavelength lensing, isolation of optical signals, super coupling, and high non-linearly are proposed and found practical applications.
The purpose of this thesis was to design, study, and interpret the extraordinary transmission (EOT) of light in subwavelength apertures placed over ENZ metamaterials. The ENZ metamaterials are utilized to enhance the polarized light through different apertures. The physics and mechanisms behind the observed transmission enhancement are often overlooked or may not be accurate. This study is an effort to reveal the nature of the mentioned phenomena using both theoretical and experimental methods.
A background for optical concepts such as optical properties of ENZ metamaterials, hybridization of propagating and localized surface plasmons in a metallic aperture, and optical behavior of subwavelength apertures are presented. The simulation, fabrication, and characterization procedures of designed samples are briefed. A presentation of simulations and physical explanation for underlying mechanisms behind the nature of the observed EOT of light through ENZ based subwavelength apertures are analyzed precisely. Moreover, the fabricated samples and detailed measurements are presented and compared with simulation results. The acquired results are in a good agreement with predictions and simulations. Fabrication of several slits (more than four) and other 3D apertures remains as an open chapter for further studies.
The purpose of this thesis was to design, study, and interpret the extraordinary transmission (EOT) of light in subwavelength apertures placed over ENZ metamaterials. The ENZ metamaterials are utilized to enhance the polarized light through different apertures. The physics and mechanisms behind the observed transmission enhancement are often overlooked or may not be accurate. This study is an effort to reveal the nature of the mentioned phenomena using both theoretical and experimental methods.
A background for optical concepts such as optical properties of ENZ metamaterials, hybridization of propagating and localized surface plasmons in a metallic aperture, and optical behavior of subwavelength apertures are presented. The simulation, fabrication, and characterization procedures of designed samples are briefed. A presentation of simulations and physical explanation for underlying mechanisms behind the nature of the observed EOT of light through ENZ based subwavelength apertures are analyzed precisely. Moreover, the fabricated samples and detailed measurements are presented and compared with simulation results. The acquired results are in a good agreement with predictions and simulations. Fabrication of several slits (more than four) and other 3D apertures remains as an open chapter for further studies.