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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Metamaterials, Surface Waves, and Their Applications

Chen, Wenchen January 2014 (has links)
Thesis advisor: Willie J. Padilla / The field of metamaterials (MMs) has garnered a great deal of attention ever since the experimental demonstration of negative refractive indexes. Such an exotic response stemmed from the engineering capability of MMs, as they can obtain almost any optical responses at any given frequency by carefully structuring the geometries. There are countless examples where MMs have posed promising results in tailoring free space radiation. However, their usage beyond this common platform is far less explored. For examples, surface electromagnetic waves, which offer great potentials for future device applications, could be an intriguing place for the further development of metamateirals. In this dissertation, we study various MM configurations where the interplay between surface waves and metamaterials has a significant impact on the device performance. Firstly, Chapter 1 introduces some fundamental concepts of metamaterials and surface electromagnetic waves, and outline the fabrication, experiments, and characterization details. In Chapter 2, we investigate whether the effective optical parameters of MMs have the exact physical meaning as those of natural substances. Two types of MM resonators are studied, and we found the thickness of the host matrix plays a crucial role in such a homogenization process. Next, we present a computational and experimental study of MMs in conjunction with a novel gigahertz/terahertz transmission line, in Chapter 3. By optimizing the coupling between the MMs and the signal, information can be encoded. Chapter 4 presents a study of designing an extremely subwavelength magnetic MM. By maximizing the effective inductance and capacitance of the structure, the final geometry obtains a strong magnetic resonance with the size of merely λₒ/2000, where λₒ is the resonant wavelength. A novel time-domain spectroscopic method is also proposed to determine the frequency-dependent permeability of the samples. In Chapter 5, we characterize two hidden channels of MM perfect absorbers : scattering and generation of surface electromagnetic waves. In particular, we unveil lossy surface waves are generated during the process resulting in an enhancement of angular absorbance. The study provides a new insight to the working principle of MMAs. In Chapter 6, we investigate complementary MM structures that exhibit strong extraordinary optical transmission with higher transmission efficiency. We discover the origin of the fundamental mode is irrelevant to the Bloch modes. Lastly, we summarize all achievements and give an outlook in Chapter 7. / Thesis (PhD) — Boston College, 2014. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Physics.
2

A study of acoustic wave propagation within curved ducting systems

Furnell, G. D. (Graham Douglas) January 1989 (has links) (PDF)
Typescript (Photocopy)
3

On the spreading of viscous dense liquid under surface waves

Fu, Sau-Chung. January 2001 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 112-114).
4

Effect of surface waves on pollutant dispersion

Loo, Hui. January 2001 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 98-100).
5

On the spreading of viscous dense liquid under surface waves

傅秀聰, Fu, Sau-chung. January 2001 (has links)
published_or_final_version / abstract / toc / Mechanical Engineering / Master / Master of Philosophy
6

Site characterization in Shelby County, Tennessee using advanced surface wave methods

Hebeler, Gregory L. 05 1900 (has links)
No description available.
7

Coded one-port acoustic surface-wave delay lines / by A.S. Burgess

Burgess, Alan Stanley January 1974 (has links)
x, 270 leaves, : ill., tables ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Electrical Engineering, 1975
8

A study of acoustic wave propagation within curved ducting systems /

Furnell, G. D. January 1989 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, 1990. / Typescript (Photocopy).
9

Coded one-port acoustic surface-wave delay lines /

Burgess, Alan Stanley. January 1974 (has links) (PDF)
Thesis (Ph.D. )--University of Adelaide, Dept. of Electrical Engineering, 1975.
10

An experimental analysis of a surface wave transmission line

McMullen, Charles Warren, January 1952 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1952. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 74-75).

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