Related papers: Metagratings for Perfect Mode Conversion in Rectan…
Metasurfaces possess vast wave-manipulation capabilities, including reflection and refraction of a plane wave into non-standard directions. This requires meticulously-designed sub-wavelength meta-atoms in each period of the metasurface…
Realizing continuous sweeping of perfect anomalous reflection in a wide angular range has become a technical challenge. This challenge cannot be overcome by the conventional aperiodic reflectarrays and periodic metasurfaces or metagratings.…
We present experimental demonstration of electronically tunable metamaterial perfect absorbers in the terahertz regime. By incorporation of active liquid crystal into strategic locations within the metamaterial unit cell we are able to…
We demonstrate the appearance of unexpected reflection resonances in corrugated dielectric waveguides. These are due to the curvature of the boundary. The effect is as strong as the ordinary Bragg resonances, and reduces the transmission…
Electromagnetic metasurfaces can be characterized as intelligent if they are able to perform multiple tunable functions, with the desired response being controlled by a computer influencing the individual electromagnetic properties of each…
Transformation optics based on conformal mapping (CM) technique provides a practical approach to designing arbitrary-shaped all-dielectric devices. However, CM may result in large impractical refractive indices unachievable by current…
Exact solutions are obtained for all the modes of wave propagation along an anisotropic cylindrical waveguide. Closed-form expressions for the energy flow on the waveguide are also derived. For extremely anisotropic waveguide where the…
Perfectly vertical grating couplers leveraging metamaterials can achieve both high coupling efficiency and minimal back reflection. The fabricability of these designs, with segmentations in both the longitudinal and transverse dimensions,…
Gradient metasurfaces have been extensively applied in recent years for enabling an unprecedented control of light beam over thin optical components. However, these metasurfaces suffer from low efficiency when it comes to bending light with…
We present the design and simulation methodology of a superconducting ridge-gap waveguide (RGWG) as a potential basis for mm-wave kinetic inductance travelling wave parametric amplifiers (KI-TWPAs). A superconducting RGWG was designed using…
Recent advances in metasurfaces have shown the importance of controlling the bianisotropic response of the constituent meta-atoms for maximum efficiency wavefront transformation. Under the paradigm of a bianisotropic metasurface, full…
Transformation optics is used to prove that a spherical waveguide filled with an isotropic material with radial refractive index n=1/r has radial polarized modes (i.e. the electric field has only radial component) with the same perfect…
This paper presents the experimental demonstration of a dual-input/dual-output reflective impedance metasurface. The design of the metasurface relies on the Method of Moments and leverages auxiliary surface waves to achieve anomalous…
In this study, we present an all-optical reflection modulator for 2$\mu$m communication band exploiting a nano-gear-array metasurface and a phase-change-material Ge$_2$Sb$_2$Te$_5$ (GST). The reflectance of the structure can be manipulated…
Topological photonics offers transformative potential for robust integrated waveguide devices due to their backscattering-immune properties. However, their integration faces two fundamental challenges: mode symmetry mismatch with…
We propose a polarization modulation scheme of electromagnetic (EM) waves through reflection of a tunable metamaterial reflector/absorber. By constructing the metamaterial with resonant unit cells coupled by diodes, we demonstrate that the…
A reconfigurable microwave reflectarray metasurface (MS) is investigated for beamforming applications. The reflected beam direction is changed by applying external dc voltages, which create a reflection phase gradient on the structure. The…
Modal phase matching (MPM) is a widely used phase matching technique in Al$_x$Ga$_{1-x}$As and other $\chi^{(2)}$ nonlinear waveguides for efficient wavelength conversions. The use of a non-fundamental spatial mode compensates the material…
Many advances in reflective metasurfaces have been made during the last few years, implementing efficient manipulations of wavefronts, especially for plane waves. Despite numerous solutions that have been developed throughout the years, a…
The dispersion properties of rectangular metallic waveguides periodically loaded by uniaxial resonant scatterers are studied with help of an analytical theory based on the local field approach, the dipole approximation and the method of…