Directive emission of red conjugated polymer embedded within zero index metamaterials

Abstract: We numerically demonstrate an impedance-matched multilayer stacked fishnet metamaterial that has zero index with flat high transmittance from 600nm to 620nm. The effective refractive index

Design and Characterization of Optical Metamaterials Using Tunable Polarimetric Scatterometry

Optical metamaterials are a class of engineered materials with a wide range of material properties and an equally wide range of anticipated applications. This research targets optical metamaterials in two ways. First, the dimensional constraints necessary to bring effective medium theory (EMT) into agreement with the already well-established transfer matrix method (TMM) modeling for a periodic, stratified (metal-dielectric) near-zero permittivity structure were determined. This provided a path to leverage the use of EMT in the design of near-zero permittivity structures and accurately predict its post-fabrication behavior. Second, the first tunable infrared (IR) Mueller matrix polarimeter-scatterometer was developed to capture the full-directional, full-polarimetric behavior of IR metamaterials. Modeling was used to determine the optimal dual rotating retarder configuration to apply to the instrument design, which was subsequently implemented. Free-space measurements corroborated the optimized design with Mueller matrix extractions having less than 1% error. The instrument was then used to measure a unique metamaterial absorber at 5 microns and captured the polarimetric behavior of a surface plasmon polariton resonance as a function of incident angle. Modeling was used to distill the s-polarized and p-polarized reflectance behavior and phase differences in the reflectances that led to the resonant signature in the measured results. As a final step, the measured results were used to predict the reflectance behavior of the material against a series of incident canonical polarization states

Planar magneto-photonic and gradient-photonic structures : crystals and metamaterials.

In the field of photonics, two new types of material structures, photonic crystals and metamaterials, are presently of great interest. Both are studied in the present work, which focus on planar magnetic materials in the former and planar gradient metamaterials in the latter. These planar periodic structures are easy to handle and integrate into optical systems. The applications are promising field for future optical telecommunication systems and give rise to new optical, microwave and radio technologies. The photonic crystal part emphasizes the utilization of magnetic material based photonic crystals due to its remarkable magneto-optical characteristics. Bandgaps tuning by magnetic field in bismuth-gadolinium-substituted lutetium iron garnet (Bi0.8 Gd0.2 Lu2.0 Fe5 O12) based one- dimensional photonic crystals are investigated and demonstrated in this work. Magnetic optical switches are fabricated and tested. Waveguide formulation for band structure in magneto photonic crystals is developed. We also for the first time demonstrate and test two- dimensional magneto photonic crystals optical. We observe multi-stopbands in two- dimensional photonic waveguide system and study the origin of multi-stopbands. The second part focus on studying photonic metamaterials and planar gradient photonic metamaterial design. We systematically study the effects of varying the geometry of the fishnet unit cell on the refractive index in optical frequency. It is the first time to design and demonstrate the planar gradient structure in the high optical frequency. Optical beam bending using planar gradient photonic metamaterials is observed. The technologies needed for the fabrication of the planar gradient photonic metamaterials are investigated. Beam steering devices, shifter, gradient optical lenses and etc. can be derived from this design

Fast Tuning of Double Fano Resonance Using A Phase-Change Metamaterial Under Low Power Intensity

In this work, we numerically demonstrate an all-optical tunable Fano resonance in a fishnet metamaterial(MM) based on a metal/phase-change material(PCM)/metal multilayer. We show that the displacement of the elliptical nanoholes from their centers can split the single Fano resonance (FR) into a double FR, exhibiting higher quality factors. The tri-layer fishnet MMs with broken symmetry accomplishes a wide tuning range in the mid-infrared(M-IR) regime by switching between the amorphous and crystalline states of the PCM (Ge(2)Sb(2)Te(5)). A photothermal model is used to study the temporal variation of the temperature of the Ge(2)Sb(2)Te(5) film to show the potential for switching the phase of Ge(2)Sb(2)Te(5) by optical heating. Generation of the tunable double FR in this asymmetric structure presents clear advantages as it possesses a fast tuning time of 0.36 ns, a low pump light intensity of 9.6 μW/μm(2), and a large tunable wavelength range between 2124 nm and 3028 nm. The optically fast tuning of double FRs using phase change metamaterials(PCMMs) may have potential applications in active multiple-wavelength nanodevices in the M-IR region