dc.contributor.advisor | Özbay, Ekmel | |
dc.contributor.author | Çubukçu, Ertuğrul | |
dc.date.accessioned | 2016-07-01T10:57:26Z | |
dc.date.available | 2016-07-01T10:57:26Z | |
dc.date.issued | 2003 | |
dc.identifier.uri | http://hdl.handle.net/11693/29304 | |
dc.description | Cataloged from PDF version of article. | en_US |
dc.description.abstract | Materials that can bend light in the opposite direction to normal (’left-handed’
materials) reverse the way in which refraction usually works-this negative refractive
index is due to simultaneously negative permeability and permittivity. Here
we demonstrate negative refraction of electromagnetic waves in a two-dimensional
dielectric photonic crystal that has a periodically modulated positive permeability
and a permeability of unity. This experimental verification of negative refraction
is a step towards the realization of a ’superlens’ that will be able to focus features
smaller than the wavelength of light. Our structure consists of a square
array of alumina rods in air. To obtain the frequency range within which the
negative refraction and the other peculiar properties incorporated with it, we
have calculated the the equal frequency contours of our photonic crystal with the
photonic plane wave expansion method. We found out that 13.7 GHz is the optimum
frequency for negative refraction. We took transmission measurements to
confirm our structure’s predicted negative refraction: we used the the interfaces
of the photonic crystal in the Γ − M direction. Our experiments were simulated
with the finite-difference time-domain method (FDTD). The negative index of
refraction was determined to be −1.94, which is close to the theoretical value of
−2.06 calculated by the FDTD method. Since we know that we have a negative
refractive material , we used our crystal to test the superlensing effect that was
predicted for negative refractive materials. We have demonstrated that the image
of two coherent point sources separated by a distance of λ/3 can be resolved.
We have extended our approach to the case with two incoherent point sources,
and we have achieved subwavelength resolution for this configuration as well.
To our knowledge, this is the first demonstration of subwavelength resolution of
electromagnetic waves in a negative index material. | en_US |
dc.description.statementofresponsibility | Çubukçu, Ertuğrul | en_US |
dc.format.extent | xii, 55 leaves | en_US |
dc.language.iso | English | en_US |
dc.rights | info:eu-repo/semantics/openAccess | en_US |
dc.subject | Photonic Crystals | en_US |
dc.subject | Equal Frequency Contours. | en_US |
dc.subject | Photonic Band Structure | en_US |
dc.subject | Subwavelength Resolution | en_US |
dc.subject | Superlens | en_US |
dc.subject | Negative Refraction | en_US |
dc.subject | Negative-Refractive Material | en_US |
dc.subject | Left-Handed Material | en_US |
dc.subject.lcc | QC793.5.P427 C83 2003 | en_US |
dc.subject.lcsh | Photons. | en_US |
dc.title | Sub-wavelength resolution in a photonic crystal superlens | en_US |
dc.type | Thesis | en_US |
dc.department | Department of Physics | en_US |
dc.publisher | Bilkent University | en_US |
dc.description.degree | M.S. | en_US |
dc.identifier.itemid | BILKUTUPB071498 | |