Line-wave waveguide engineering using Hermitian and non-Hermitian metasurfaces.

Line waves (LWs) refer to confined edge modes that propagate along the interface of dual electromagnetic metasurfaces while maintaining mirror reflection symmetries. Previous research has both theoretically and experimentally investigated these waves, revealing their presence in the microwave and terahertz frequency ranges. In addition, a comprehensive exploration has been conducted on the implementation of non-Hermitian LWs by establishing the parity-time symmetry.

Penrose tiling-inspired graphene-covered multiband terahertz metamaterial absorbers.

In this work, we propose two different graphene-covered nanostructured metamaterial absorbers inspired by Penrose tiling. These absorbers allow spectrally tunable absorption within the terahertz spectrum corresponding to 0.2-20 THz.

Modeling and analysis of high-sensitivity refractive index sensors based on plasmonic absorbers with Fano response in the near-infrared spectral region.

In this paper, we present various optical metamaterial nanoabsorbers with the aim of improving the refractive index sensitivity using the Fano response. The proposed absorbers consist of various parasitic elements such as single cross, broken cross, Jerusalem cross, and also single L and double L models. We numerically study their absorption and reflection using the three-dimensional finite-difference time-domain method and calculate the sensitivity and figure of merit (FOM) in every absorption peak (reflection dip).

Dispersion-engineered microstructured optical fiber for mid-infrared supercontinuum generation.

Due to the large scientific and technical interest in the mid-infrared (MIR) spectral region, and the limitations of MIR light sources, we focus on the generation of a broad supercontinuum inside a short piece of AsSe microstructured optical fiber (MOF) with a square lattice. This is accomplished by filling the holes in the innermost ring of the proposed MOF with GeAsSe to produce ultraflat and near-zero dispersion. Simulations reveal that, by launching 100 fs input pulses centered at λ=6.

Super-flat coherent supercontinuum source in AsSe chalcogenide photonic crystal fiber with all-normal dispersion engineering at a very low input energy.

We numerically report super-flat coherent mid-infrared supercontinuum (MIR-SC) generation in a chalcogenide AsSe photonic crystal fiber (PCF). The dispersion and nonlinear parameters of AsSe chalcogenide PCFs by varying the diameter of the air holes are engineered to obtain all-normal dispersion (ANDi) with high nonlinearities. We show that launching low-energy 50 fs optical pulses with 0.

Midinfrared supercontinuum generation via As2Se3 chalcogenide photonic crystal fibers.

Using numerical analysis, we compare the results of optofluidic and rod filling techniques for the broadening of supercontinuum spectra generated by As2Se3 chalcogenide photonic crystal fibers (PCFs). The numerical results show that when air-holes constituting the innermost ring in a PCF made of As2Se3-based chalcogenide glass are filled with rods of As2Se3-based chalcogenide glass, over a wide range of mid-IR wavelengths, an ultra-flattened near-zero dispersion can be obtained, while the total loss is negligible and the PCF nonlinearity is very high. The simulations also show that when a 50 fs input optical pulse of 10 kW peak power and center wavelength of 4.