Designing And Analysis Of 2 Dimensional And 3 Dimensional Negative Refractive Index Materials

Metamaterials gain a considerable attention in last few years. Engineered materials with high refractive index values brought a change in the field of materials science due to their fascinate properties which are not found in natural materials. The study of designing of metamterials not only important to produce new kinds of metamaterials but also important to reduce the complexity faced by the researchers before. The use of negative refractive index materials in imaging, compact optical circuits and in various other devices makes this class of materials important. Thus breakthroughs in this class of electromagnetic materials are related with the progress in the development of physics driven designs, novel fabrications and characterizations methods. Novel designs of metamaterials are interesting from both fundamental and practical point of view. New frontiers are being explored to overcome the challenges to design metamaterials to operate them at optical frequency.Metamaterial designing has been a topic of interest among the research community to widen the applicability of electromagnetic materials. New innovative structures have been reported showing performance improvement in terms of size bandwidth, frequency bandwidth, ease of fabrication, tuning capability etc. In this research, the main focus was on designing and analyzing of novel 2 dimensional and 3 dimensional double negative refractive index materials.Initially, A-shape novel metamaterial structure which simultaneously exhibits negative permittivity and negative permeability has been constructed. An electromagnetic wave simulation was performed, and the results show that the proposed metamaterial unit cell is capable of achieving a negative refractive index over a brad frequency band ranges from 1.0 GHz to 6.20 GHz. Furthermore, a left hand prism was designed composed of metamaterial unit cells. Simulation of the left hand prism proves the presence of a negative refractive index. Due to the simple geometry, the proposed design is easy to fabricate compared to the complex structures reported to date, and could be used in various applications.Later on, a negative refractive index tunable metamaterial based on F-Shape structure which is capable of achieving dual-band negative permeability and permittivity, thus dual-band negative refractive index has been designed and analyzed. An electromagnetic simulation was performed and effective media parameters were retrieved. Numerical investigations show clear existence of two frequency bands in which permeability and permittivity both are negative. The two negative refractive index bandwidths are from 23.8 GHz to 24.1 GHz and from 28.3 GHz to 34.9 GHz, respectively. The geometry of the structure is simple so it can easily be fabricated. The proposed structure can be used in multiband and broad band devices, as the band range in second negative refractive index region is 7 GHz, for potential applications instead of using complex geometric structures and easily tuned by varying the separation between the horizontal wires.At the end, a novel 3 dimensional metamaterial, constructed with wires, spheres and hollow slabs (WSHS) will be presented which simultaneously exhibits negative permittivity and permeability. An electromagnetic wave simulation is performed based on the proposed metamaterial and shows that a negative refractive index is achieved for this metamaterial. Adjusting the lattice constant of the unit cell is an easy way to manipulate the frequency of negative index of this structure. A left-hand material prism is designed composed of metamaterial unit cells and the simulation on the proposed prism proves the left-hand behavior of the designed metamaterial.