We propose multi-band metamaterial absorbers at microwave frequencies. The design, the analysis, fabrication, and measurement of working in multiple bands are presented. numerical simulations experiments anechoic chamber were performed. consist an delicate arrangement donut-shape resonators with different sizes a metallic background plane, separated by dielectric. near-perfect absorptions dual, triple quad peaks persistent polarization independence, effect angle incidence for both TE TM...

Abstract Perfect metamaterial absorber (PMA) can intercept electromagnetic wave harmful for body in Wi-Fi, cell phones and home appliances that we are daily using provide stealth function military fighter, tank warship avoid radar detection. We reported new concept of water droplet-based PMA absorbing perfectly with water, an eco-friendly material which is very plentiful on the earth. If arranging droplets particular height diameter surface through wettability surface, meta-properties GHz...

Using a planar metamaterial, which consists of two silver strips, we theoretically demonstrate the plasmonic electromagnetically-induced transparency (EIT)-like spectral response at optical frequencies. The strips serve as bright modes, and are excited strongly by incident wave. Based on weak hybridization between highly-dispersive EIT-like appears in our scheme. Moreover, group index is higher than that another scheme utilizes strong coupling dark modes.

We propose polarization-independent and dual-broadband metamaterial absorbers at microwave frequencies. This is a periodic meta-atom array consisting of metal-dielectric-multilayer truncated cones. demonstrate not only one broadband absorption from the fundamental magnetic resonances but additional in high-frequency range using third-harmonic resonance, by both simulation experiment. In simulation, was over 90% 3.93-6.05 GHz, 11.64-14.55 GHz. The corresponding experimental bands were...

Metamaterials are artificially-engineered materials, possessing properties which not readily observable in materials existing nature. Since they show very novel such as left-handed behavior, negative refractive index, classical analog of electromagnetically-induced transparency, extraordinary transmission, Doppler effect, and so on, can be used for perfect lens, invisibility cloaking, absorption etc. Metamaterial-based absorbers (MMPAs) promising candidates the practical application...

Using a planar and flexible metamaterial (MM), we obtained the low-frequency perfect absorption even with very small unit-cell size in snake-shape structure. These shrunken, deep-sub-wavelength thin MM absorbers were numerically experimentally investigated by increasing inductance. The periodicity/thickness (the figure of merit for absorption) is achieved to be 10 2 single-snake-bar 5-snake-bar structures, respectively. ratio between periodicity resonance wavelength (in mm) close 1/12 1/30...

Antireflection (AR) coatings that exhibit multifunctional characteristics, including high transparency, robust resistance to moisture, hardness, and antifogging properties, were developed based on hollow silica–silica nanocomposites. These novel nanocomposite with a closed-pore structure, consisting of silica nanospheres (HSNs) infiltrated an acid-catalyzed sol (ACSS), fabricated using low-cost sol–gel dip-coating method. The refractive index the was tailored by controlling amount ACSS into...

We numerically and experimentally investigated dual-band absorption of sandwich-structure metamaterials which include periodic metal coupled rings at the front separated from plane back by a dielectric layer. The properties are demonstrated in both GHz mid-IR regimes electromagnetic (EM) wave. perfect absorber with polarization independence is observed under normal incidence. In order to understand EM absorber, plasmonic excitation was clarified for peaks. Finally, connecting rings,...

Plasmonic electromagnetically-induced transparency (EIT) can be excited by a single optical field unlike EIT in atom system, since the coupling between bright and dark modes is inherently induced through near-field interaction metamaterials. As result, complexity of experimental realization reduced significantly, while tunability lost inevitably.We suggest scheme that plasmonic possible to actively manipulated even field. The are selective either coupled or uncoupled, depending on angle...

We propose a dual-band metamaterial perfect absorber at microwave frequencies. Using planar metamaterial, which consists of periodic metallic donut-shape meta-atoms the front separated from plane back by dielectric layer, we demonstrate multi-plasmonic high-frequency absorptions induced third-harmonic as well fundamental magnetic resonances. The origin absorption was elucidated. It also found that dual peaks are persistent with varying polarization.

Magnetic resonance is considered to be a necessary condition for metamaterial perfect absorbers, and dual-band absorbers can composed of pair metallic layers with anti-parallel surface currents. We designed fabricated tunable absorber based on extraordinary-optical-transmission (EOT) effect Fabry-Perot cavity resonance. The idea the mechanism are completely different from near-field interaction. important advantage our structure that we switch single-band by changing distance between two...

We numerically and experimentally studied an ultrathin broadband perfect absorber by enhancing the bandwidth with embedded resistors into metamaterial structure, which is easy to fabricate in order lower Q-factor using multiple resonances patches of different sizes. analyze absorption mechanism terms impedance matching free space through distribution surface current at each resonance frequency. The magnetic field, induced antiparallel currents, formed strongly direction opposite incident...

We have investigated the generalized susceptibility $\ensuremath{\chi}(\mathbf{q})$ and Fermi-surface-nesting of ferromagnetic shape-memory alloy ${\mathrm{Ni}}_{2}\mathrm{MnGa}.$ As temperature is lowered below Curie point, a premartensitic transformation takes place when magnetization reaches about 84% its $T=0$ saturated value. show that spin-split band structure near this gives rise in to prominent peak at $\mathbf{q}=(\frac{1}{3},\frac{1}{3},0)(2\ensuremath{\pi}/a),$ corresponding...

A comprehensive characterization of the compound ${\mathrm{Fe}}_{2}\mathrm{VAl}$ was carried out. Samples grown by arc melting or Bridgman method have Al and Fe deficiencies up to 5 at. %. Czochralski-grown samples were rich deficient. X-ray diffraction implies appreciable antisite disorder in all our samples. Fourier-transform infrared (FTIR) spectroscopy measurements showed that carrier density scattering time had little sample-to-sample variation temperature dependence for...

In general metamaterial perfect absorber, the single meta-pattern makes absorption band. Therefore, multi-absorption bands need corresponding kinds of meta-patterns. Here, we introduce triple-band absorber utilizing only kind pattern. We also demonstrate mechanism triple absorption. The first and second were induced by fundamental magnetic resonance major minor axes, respectively, cut-wire bar. third peak was caused third-harmonic axis. Additionally, unexpected band formed, which overlapping...

The recent observation of extremely large magnetoresistance (MR) in the transition-metal dichalcogenide MoTe2 has attracted considerable interest due to its potential technological applications as well relationship with novel electronic states predicted for a candidate type-II Weyl semimetal. In order understand origin MR, structure MoTe2-x (x = 0.08) is systematically tuned by application pressure and probed via Hall longitudinal conductivities. With increasing pressure,...

The generalized susceptibility for rare-earth nickel boride carbides has been calculated using the normal-state electronic structure. Peaks in occur near wave vectors corresponding to those observed incommensurate spin density waves ${\mathrm{HoNi}}_{2}$${\mathrm{B}}_{2}$C between approximately 4.7 and 6.0 K [A. I. Goldman et al., Phys. Rev. B 50, 9668 (1994)].

We have investigated the effects of atomic disorder on electronic structure and some physical properties ${\text{Co}}_{2}\text{CrAl}$ Heusler alloy (HA) films. Flash evaporation onto glass substrates at different temperatures (from 150 to 750 K) postannealing various were employed manipulate structural order in HA The $L{2}_{1}$-ordered films exhibit magnetic, transport, optical close those bulk ordered sample. Increase...

A broken symmetry is generally believed to be a prerequisite for plasmonic electromagnetically-induced transparency (EIT), since the asymmetry allows excitation of otherwise forbidden dark mode. Nevertheless, according picture magnetic plasmon resonance (MPR)-mediated EIT, we show that EIT can achieved even in symmetric structures based on second-order MPR. This not only sharpens our understanding existing concept, but also provides profound insight into coherent interference near-field zone.

Cobalt (Co) antidot arrays with different lattice geometries, square and rhomboid structures were fabricated their magnetic reversal properties studied by scanning-electron microscopy (SEM), magneto-optic Kerr effect, force (MFM). Different symmetries induced the corresponding anisotropies changing easy hard axes. The nearest-neighbor rule is not applicable in case of lattice, while inclusion theory is. These results are from those previous investigations. differences due to sizes spacing’s...

We experimentally demonstrated a controllable electromagnetically induced transparency (EIT)-like spectral response at microwave frequencies in planar metamaterial consisting of two identical split-ring resonators (SRRs) with side-by-side symmetry. In our scheme, phase coupling between the SRRs (serving as bright mode), which were excited strongly by incident wave, was employed, and it found that EIT-like could be controlled simply adjusting angle. Thus, scheme may used for...