The shell on the nano-magnetic absorber can prevent oxidation, which is very important for its practical utilization. Generally, the nonmagnetic shell will decrease the integral magnetic loss and thus weaken the electromagnetic absorption. However, maintaining the original absorption properties of the magnetic core is a major challenge. Here, we designed novel and facile CoxFey@C composites by ...

Absorption of electromagnetic waves in a medium is generally manipulated by controlling the frequency dispersion of constitutive parameters. However, it is still challenging to gain the desired constitutive parameters for customized absorption over a broad frequency range. Here, by virtue of spoof surface plasmonic polaritons (SPPs), we demonstrate capabilities of the spatial k-dispersion engin...

Components manipulation and structure engineering have shown powerful approaches for tailoring electromagnetic (EM) parameters. However, the integration of controllable architectural compositional complexity into one multiple-layer heterostructure seems significantly effective but remains a considerable challenge, correlative quantized modulation EM parameters is scarce. Herein, three types met...

We study electromagnetic forces and torques on a discrete spherical invisibility cloak under time-harmonic illumination. We consider the influence of material absorption and losses, and we show that while the impact of absorption on the optical force remains confined to frequencies near the absorption peak, its impact on the electromagnetic torque experienced by the cloak is spectrally broader ...

We demonstrate theoretically that electromagnetically induced transparency can be achieved in metamaterials, in which electromagnetic radiation is interacting resonantly with mesoscopic oscillators rather than with atoms. We describe novel metamaterial designs that can support a full dark resonant state upon interaction with an electromagnetic beam and we present results of its frequency-depend...

In this work, cobalt/polypyrrole (Co/PPy) nanocomposites were prepared via an in situ oxidation polymerization of pyrrole in an aqueous dispersion of Co nanoparticles (NPs). The Co/PPy nanocomposites showed good electromagnetic properties because of the coexistence of magnetic loss and dielectric loss to electromagnetic waves. The electromagnetic wave absorbing bandwidth (reflection loss < -10 ...

With the conservation of power, a phase diagram defined by amplitude square and phase of scattering coefficients for each spherical harmonic channel is introduced as a universal map for any passive electromagnetic scatterers. Physically allowable solutions for scattering coefficients in this diagram clearly show power competitions among scattering and absorption. It also illustrates a variety o...

A metamaterial electromagnetic wave absorber consisting of a big circular ring patch with four smaller suppression circular rings is presented in this report. The metamaterial electromagnetic wave absorber introduces the concept of size reduction by suppressing the resonance frequency. An FR4 substrate was used and the incidental wave angles were varied from 0 0 to 60 0 . Simulations results sh...

Iron oxides/reduced graphene oxide composites were synthesized by facile thermochemical reactions of graphite oxide and FeSO4 · 7H2O. By adjusting reaction temperature, α-Fe2O3/reduced graphene oxide and Fe3O4/reduced graphene oxide composites can be obtained conveniently. Graphene oxide and reduced graphene oxide sheets were demonstrated to regulate the phase transition from α-Fe2O3 to Fe3O4 v...

The electromagnetic superabsorber that has larger absorption cross section than its real size may be a novel photothermal device with improved solar energy conversion rates. Based on a transformation optical approach, the material parameters for a two-dimensional (2D) metamaterial-assisted electromagnetic superabsorber with arbitrary geometries are derived and validated by numerical simulation....