Related papers: Tunable mid-infrared coherent perfect absorption i…
The inter-band optical absorption in graphene characterized by its fine-structure constant has a universal value of 2.3\% independent of the material parameters. However, for several graphene-based photonic applications, enhanced optical…
In this paper, we proposed a theoretical model in the far-infrared and terahertz (THz) bands, which is a dumbbell-shaped graphene metamaterial arrays with a combination of graphene nanorod and two semisphere-suspended heads. We report a…
Conjugate metamaterials, in which the permittivity and the permeability are complex conjugates of each other, possess the elements of loss and gain simultaneously. By employing a conjugate metamaterial with a purely imaginary form, we…
The GW self-energy may become computationally challenging to evaluate because of frequency and momentum convolutions. These difficulties were recently addressed by the development of the multipole approximation (MPA) and the W-av methods:…
Recent emergence of metasurfaces has enabled the development of ultra-thin flat optical components through different wavefront shaping techniques at various wavelengths. However, due to the non-adaptive nature of conventional metasurfaces,…
Graphene is an ideal material for integrated nonlinear optics thanks to its strong light-matter interaction and large nonlinear optical susceptibility. Graphene has been used in optical modulators, saturable absorbers, nonlinear frequency…
We demonstrate the ability to control the scattering properties of a two-dimensional wave-chaotic microwave billiard through the use of tunable metasurfaces located on the interior walls of the billiard. The complex reflection coefficient…
A tunable metasurface absorber is presented in this work using an optically-programmable capacitor as the tuning element. The tuning element does not employ conventional semiconductor technologies to operate but rather a bases its tuning by…
Enhanced optical absorption in two-dimensional (2D) materials has recently moved into the focus of nanophotonics research. In this work, we present a gain-assisted method to achieve critical coupling and demonstrate the maximum absorption…
The unique terahertz properties of graphene has been identified for novel optoelectronic applications. In a graphene sample with bias voltage added, there is an enhanced absorption in the far infrared region and a diminished absorption in…
A fully integrated waveguide-based, efficient surface plasmon coupler composed of a realistic non-tapered dielectric waveguide with graphene patches and sheet is designed and optimized for the infrared. The coupling efficiency can reach…
This article presents a novel approach for designing dual-band absorbers based on graphene and metallic metasurfaces for terahertz and mid-infrared regimes, respectively. The absorbers are composed of a two-dimensional (2D) array of square…
The field of coherent electronics aims to advance electronic functionalities by utilizing quantum coherence. Here, we demonstrate a viable and versatile methodology for controlling electron dynamics optically in graphene nanoribbons. In…
Effective control of terahertz radiation requires the development of efficient and fast modulators with a large modulation depth. This challenge is often tackled by using metamaterials, artificial sub-wavelength optical structures…
Thermo-optical properties of the nanodisc and metal hole array plasmonic perfect absorber (PPA) metasurfaces were designed and characterised at midinfrared wavelengths. Both, light emitter and detector systems are highly thought after for…
Plasmon oscillations have been intensively studied for more than forty years in conventional two-dimensional electron gas systems in order to find new alternatives to the vacuum devices based on the Smith-Purcell effect in the far-infrared…
Borophene has recently attracted significant attention as an emerging two-dimensional monoelemental material for refractive index sensing because of its ultra-high surface-to-volume ratio and outstanding surface sensitivity. However,…
We develop a Coherent Perfect Absorption (CPA) protocol for cases where scale invariance is violated due to the presence of nonlinear mechanisms. We demonstrate, using a microwave setting that lacks geometrical symmetries, that the…
We designed and demonstrated a multi-spectral programmable perfect absorber that exploits two different phase-change materials. This programmability is possible by resonantly coupling two phase change materials, a Ge2Sb2Te5 layer to…
In this letter, we report a method to control reflection phase of microwaves using electrically tunable graphene devices. The device consists of mutually gated large-area graphene layers placed at a quarter-wave distance from a metallic…