Gerçek solak materyaller kullanarak negatif kırılma elde edilmesi

AbstractNEGATIVE REFRACTION USING TRUELEFT-HANDED METAMATERIALSKoray AydınM. S. in PhysicsSupervisor: Prof. Dr. Ekmel ÖzbaySeptember 2004Left-handed materials and negative refraction attracted a great amount ofattention in recent years due to their unique physical properties. It is possible toobtain a left-handed material by combining a novel artificial structure (split ringresonator) and a wire structure periodically. We investigated the transmission andreflection properties of split ring resonators (SRR), wires and compositemetamaterials consisting of SRR and wire structures. We have successfullydemonstrated true left-handed behavior in free space with a high transmission peak(-1.2 dB). This is the highest transmission peak reported for a left-handed material.The left-handed transmission band coincides exactly with the region where bothdielectric permittivity and magnetic permeability have negative values. Weproposed and demonstrated a new method to distinguish the magnetic resonance ofthe SRR structures.iWe experimentally confirmed that composite metamaterial has a negativerefractive index, at the frequencies where left-handed transmission takes place.Phase shift between consecutive numbers of layers of CMM is measured andphase velocity is shown to be negative at the relevant frequency range. Refractiveindex values obtained from the refraction experiments (-1.87) and the phase shiftexperiments (-1.78) are in good agreement.Keywords: Left-Handed Material, Composite Metamaterial, Split Ring Resonator,Negative Permittivity, Negative Permeability, Effective Medium Theory, PhotonicBand Gap, Negative Refraction, Negative Phase Velocity.ii