Listar por autor UPNA "Navarro Cía, Miguel"
Mostrando ítems 21-40 de 59
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Experimental demonstration of phase resonances in metallic compound gratings with subwavelength slits in the millimeter wave regime
We provide experimental evidence of phase resonances in metallic periodic structures in which each period comprises several subwavelength slits of the same width. We have analyzed and measured the response of these ... -
Exploiting the dispersion of the double-negative-index fishnet metamaterial to create a broadband low-profile metallic lens
Metamaterial lenses with close values of permittivity and permeability usually display low reflection losses at the expense of narrow single frequency operation. Here, a broadband low-profile lens is designed by exploiting ... -
Extraordinary THz transmission with a small beam spot: the leaky wave mechanism
The discovery of extraordinary optical transmission (EOT) through patterned metallic foils in the late 1990s was decisive for the development of plasmonics and cleared the path to employ small apertures for a variety of ... -
Extraordinary transmission and left-handed propagation in miniaturized stacks of doubly periodic subwavelength hole arrays
Metallic plates embedded between dielectric slabs and perforated by rectangular arrays of subwavelength holes with a dense periodicity in one of the directions support extraordinary transmission (ET) phenomena, viz. strong ... -
Far-field and near-field physics of extraordinary THz transmitting hole-array antennas
Despite three decades of effort, predicting accurately extraordinary transmission through subwavelength hole arrays has proven challenging. The lack of quantitative design and modeling capability to take into account ... -
Frozen mode from hybridized extraordinary transmission and Fabry-Perot resonances
Frozen modes arising in stacked subwavelength hole arrays are studied in detail. Their origin is proved to be connected with the interaction between the extraordinary transmission resonance and the Fabry–Perot cavity mode. ... -
Hedgehog subwavelength hole arrays: control over the THz enhanced transmission
By backing or sandwiching a holey metal layer with or between isotropic dielectric slabs, additional peaks of transmission within the long-wavelength regime arise as a result of the induced transverse magnetic (TM) or ... -
Lensing system and Fourier transformation using epsilon-near-zero metamaterials
Metamaterials and metastructures with effective relative permittivity near zero exhibit unusual wave properties such as uniform phase distributions across such domains. Here we discuss the possibility of using ε-near-zero ... -
Lentes metálicas basadas en el fenómeno de transmisión extraordinaria para conseguir índices de refracción negativos
In this communication we report plano-concave and bi-concave metamaterial lenses based on the close stack of subwavelegnth hole arrays. Contrary to what is expected from cut-off holes, an engineered array of holes ... -
Low profile THz periodic leaky-wave antenna
In this work, a 0.566THz flat leaky-wave antenna, consisting of a central λ0/2 slot surrounded by straight parallel wedge corrugations, is numerically and experimentally analyzed. Simulations show a moderately high gain ... -
Mechanical 144GHz beam steering with all-metallic epsilon-near-zero lens antenna
An all-metallic steerable beam antenna composed of an ε-near-zero (ENZ) metamaterial lens is experimentally demonstrated at 144 GHz (λ0 = 2.083 mm). The ENZ lens is realized by an array of narrow hollow rectangular waveguides ... -
Metal 3D printed D-Band waveguide to surface wave transition
The coupling efficiency between free space waves and surface waves is low, narrowband, or both. Highly efficient broadband (better than 20% fractional bandwidth) coupling from waveguide modes can be achieved through ... -
Mid-infrared plasmonic inductors: enhancing inductance with meandering lines
We present a mid-infrared inductor that when applied to an extraordinary transmission hole array produces a strong redshift of the resonant peak accompanied by an unprecedented enlargement of the operation bandwidth. The ... -
Millimeter-wave phase resonances in compound reflection gratings with subwavelength grooves
Experimental evidence of phase resonances in a dual-period reflection structure comprising three subwavelength grooves in each period is provided in the millimeter-wave regime. We have analyzed and measured the response ... -
Negative refraction in a prism made of stacked subwavelength hole arrays
Metamaterial structures are artificial materials that show unconventional electromagnetic properties such as negative refraction index, perfect lenses, and invisibility. However, losses are one of the big challenges to be ... -
Negative refraction through an extraordinary transmission left-handed metamaterial slab
In this work we present numerical and experimental results of negative refraction through a negative index metamaterial based on miniaturized extraordinary transmission stacked subwavelength hole arrays, also known as ... -
New regimes to achieve enhanced transmission through subwavelength hole arrays
In this communication we present millimetre- and THz-waves experimental confirmation of enhanced transmission through subwavelength hole arrays with rectangular lattice when the incident electric field is parallel to ... -
Planar holographic metasurfaces for terahertz focusing
Scientists and laymen alike have always been fascinated by the ability of lenses and mirrors to control light. Now, with the advent of metamaterials and their two-dimensional counterpart metasurfaces, such components can ... -
Planoconcave lens by negative refraction of stacked subwavelength hole arrays
This work presents the design of a planoconcave parabolic negative index metamaterial lens operating at millimeter wavelengths fabricated by using stacked subwavelength hole arrays. A staircase approximation to the ideal ... -
Plasmonics and metamaterials at terahertz frequencies
The research presented in this manuscript falls under the framework of metamaterials and plasmonics. It is mainly focused on applications at terahertz (THz) frequencies, a spectral band located between microwaves and ...