相关论文: Metallic helix array as a broadband wave plate
We designed a cut-wire-pair metasurface that works as a transparent terahertz half-wave plate, by matching the electric and magnetic resonances of the structure. Due to the impedance matching nature of the resonances, a large transmission…
The transmission of linearly and circularly polarized waves are studied both theoretically and experimentally for chiral metasurfaces formed by arrays of metallic square helices. The helical particles of the metasurfaces are constructed of…
We investigate the capabilities of hyperbolic metamaterials (HMs) to couple near-fields (i.e., evanescent waves) emitted by a two-dimensional periodic array of electric dipoles to propagating waves. In particular, large order Floquet…
Light propagation in all-dielectric rod-type metamaterials is studied theoretically. The electric and magnetic dipole moments of the rods are derived analytically in the long-wavelength limit. The effective permittivity and permeability of…
This study theoretically and experimentally investigates the transmission properties of a metamaterial slab comprised of two layers of metallic fish-scale structure arrays and a sandwiched dielectric layer. Calculations show that the…
In this work, we study the realization of realistic polarization transformers formed by long metallic helices. To this end, we propose a new homogenization model to characterize the propagation of electromagnetic waves in medium formed by…
We introduce a solid material that is itself invisible, possessing identical electromagnetic properties as air (i.e. not a cloak) at a desired frequency. Such a material could provide improved mechanical stability, electrical conduction and…
We theoretically study the transmission properties of a stack of metallic metamaterials and show that is able to achieve a perfect transmission selectively exhibiting broadband ($Q<10$) or extremely narrowband ($Q>10^5$) polarization…
Metallic structures with periodic array of slits are well-known to lead to extraordinary power transmission, when slits have dimensions much less than the wavelength of incident optical wave. Excellent power transmission originates from…
We develop a theory to compute and interpret the photonic band structure of a periodic array of metallic helices for the first time. Interesting features of band structure include the ingenuous longitudinal and circularly polarized…
A new mechanism of Bragg reflection is identified, one that, remarkably, occurs in a uniform medium and relies on resonant tuning of the medium's parameters. Due to uniformity, reflection ensues over a broad wavelength range, much like a…
We study optical wave manipulations through high-index dielectric metalattices in both diffractionless metasurface and diffractive metagrating regimes. It is shown that the collective lattice couplings can be employed to tune the excitation…
The quasi-optical modulation of linear polarization at millimeter and sub-millimeter wavelengths can be achieved by using rotating half wave plates (HWPs) in front of polarization sensitive detectors. Large operational bandwidths are…
Metalenses are attracting a large interest for the implementation of complex optical functionalities in planar and compact devices. However, chromatic and off-axis aberrations remain standing challenges. Here, we experimentally investigate…
We describe a broadband optical device that is capable of rotating the polarization plane of a linearly polarized light at any desired angle over a wide range of wavelengths. The device is composed of a sequence of half-wave plates rotated…
A charge carrier confined in a quasi-one-dimensional semiconductor helical nanostructure in the presence of an electric field normal to the axis of the helix is subjected to a periodic potential proportional to the strength of the field and…
We show that a metallic plate with fractal-shaped slits can be homogenitized as a plasmonic metamaterial with plasmon frequency dictated by the fractal geometry. Owing to the all-dimensional subwavelength nature of the fractal pattern, our…
We theoretically demonstrate the formation of different kinds of two-dimensional split-ring arrays in both triangular and square lattices by one-step holographic interference. The slit width of the split-ring can be adjusted by proper…
We show that polarization states of electromagnetic waves can be manipulated easily using a single thin uniaxial crystal plate. By performing a rotational transformation of the coordinates and controlling the thickness of the plate, we can…
Motivated by the importance of lattice structures in multiple fields, we investigate the propagation of flexural waves in a thin woven plate augmented with two classes of metastructures for wave mitigation and guiding, namely metabarriers…