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Metamaterials have attracted tremendous amount of interests owing to their tempting electromagnetic responses. Based on the metamaterials, many novel practical electromagnetic devices have been realized in the microwave, terahertz, and optical frequencies. Recently, a new type of metamaterial filter has attracted growing attention. Based on the method of hybrid multiple resonances, the metamaterial...
Toroidal dipolar response in a metallic metastructure, composed of double flat rings, is utilized to manipulate the radiation pattern of a single dipolar emitter (e.g., florescent molecule/atom or quantum dot). Strong Fano-type radiation spectrum can be obtained when these two coupling dipoles are spatially overlapped, leading to significant radiation suppression (so-called nonradiating source) attributed...
A novel dual-band EBG-based Multiple-input multiple-output (MIMO) antenna system with high isolation performance for wireless local area network (WLAN) applications is proposed. The MIMO antenna comprises of two broadband printed slot antennas fed by a coplanar waveguide (CPW) feed line. When the antennas are placed at closer spacing, mutual coupling comes into existence deteriorating the performance...
Terahertz Photonics is an emerging field with a great amount of potential science and applications. Functional optical technologies to control the amplitude, phase and polarization of Terahertz waves are crucial for advancing the THz technology. In this work, we study the coherent perfect absorption (CPA) [1] of a chiral structure and show its potential use as polarization control for THz waves.
The plasmonic metamaterial perfect absorber (MPA) is a recently developed branch of metamaterial which exhibits nearly unity absorption within certain frequency range [1–6]. The optically thin MPA possesses characteristic features of angular-independence, high Q-factor and strong field localization that have inspired a wide range of applications including electromagnetic wave absorption [3, 7, 8],...
Design and characterization of periodic dielectric or metallic structures such as photonic crystals and plasmonic metamaterials with unique electromagnetic responses have stimulated extensive attention due to the unusual physical phenomena and the potential applications in electromagnetic devices. These artifical materials are based on the original concept of manipulating electromagnetic waves by...
In this talk, we numerically demonstrate the potential of a hyperbolic medium in the design of an efficient metamaterial antenna enhancing the second harmonic generation of a nano-object, with an otherwise hidden nonlinear signature through a metamaterial-assisted access to evanescent second-harmonic fields. In further discussion, we consider the second harmonic generation from the metamaterial itself...
A recurring theme in optics and photonics is the ability of metal nanostructures to imbue artificial materials with new functions. Metallic nano-antennas [1], so-called meta-atoms, are the building blocks of such metamaterials that boast unusual linear [2, 3] and nonlinear [4– 6] characteristics not observed in natural materials. Recently, nonlinear metamaterials have generated considerable excitement;...
Metamaterials are artificially structured nanomaterials that have enabled unprecedented phenomena such as negative refraction, zero index and extreme anisotropy. The acoustic analogue to electromagnetic metamaterials has already been investigated, and the possibility of extending the metamaterials concept to acoustic waves has already been proved [1–6]. Although the attempts of designing acoustic...
Electromagnetic wave induced forces have been extensively studied for decades. It has been well known that for an electromagnetic wave propagating in vacuum the photons carrying momentum exert a positive photon pressure on an object. However, a metamaterial can have a negative effective refractive index, in which case the wave vector is directed towards the source of radiation. In such a medium, should...
We propose a reflective linear polarization converter with broadband and high-efficiency using ladder-shaped resonator (LSR) structure metamaterial (MM) based on multi-reflection interference theory. Three resonances generated by LSRs contribute to the expansion of working frequency range while the interference theory is employed to explain the characteristic of high-efficiency polarization conversion...
The extraordinary properties of acoustic (random) metamaterials, such as negative refractive index, originate from low frequency resonances of sub-wavelength particles. While most of these functional materials are fabricated by mechanical engineering, we have recently shown that soft matter techniques coupled with microfluidics open a new synthesis route for acoustic metamaterials [1]. As a demonstration,...
In this work, the nonlinear response from metallic metamaterials is characterized by a finite-difference time-domain solution to the Maxwell-hydrodynamic equations. The spatial locations of E-fields (and electric currents) are interleaved with that of magnetic fields. The electron charge is at the center of Yee grids. The current continuity equation connects Maxwell and hydrodynamic equations. For...
Recently THz antenna is becoming more interesting for the researcher because of huge applications in the areas of remote sensing, imaging, Radar and satellite communications. With these developments tremendous opportunities are available to obtain the super quality images, high speed and large data communications. THz antenna design inherits many challenges starting from fabrication to interaction...
For many years, the (quantum) theory of light in condensed matter has been focused on describing classical and quantum phenomena on scales larger than the wavelength and regarded the material in which light propagates, is absorbed or emitted from in terms of effective parameters such as a refractive index. Recent progress in transformation optics and nanophotonics and metamaterials physics, however,...
We experimentally demonstrate the enhancement of the spontaneous emission rate of GaAs quantum wells (QWs) embedded in rolled-up metamaterials. We investigate the spontaneous emission lifetime of semiconductor QW heterostructures which are directly integrated inside rolled-up microtubes (RMTs) with hyperbolic dispersion. RMTs are prepared by self-rolling of strained metal-semiconductor layer systems...
Metamaterials have introduced many relevant new possibilities in the manipulation of light, microwaves, sound waves, and other systems. In many cases, the design and optimization of metamaterials has been achieved in conjunction with the mathematical technique of transformation optics, which allows one to guide rays of light or electromagnetic fields along desired directions. This is achieved by tailoring...
The nitrogen-vacancy (NV) center in diamond is attracting a lot of attention in quantum information processing community. A spin system in the NV center is positioned in a clean and well-controlled environment. As a result, it shows outstanding performance as quantum memory, even at room temperature, allows for spin control with a single shot optical readout, and offers a possibility of building quantum...
In this talk, we will present a wideband microstrip antenna in dual-layer substrates. As is well known that, conventional low-profile microstrip antennas have the drawback of their inherent narrow bandwidth characteristics. As a result, it seriously limited their usages in high data rate wireless transmission applications, such as high precision radar detection, multi-inputmulti- output (MIMO) systems...
In this letter, a composite metasurface for end-fire scattering is designed, fabricated and characterized. Based on the principle of scattering cancelation and method of end-fire antenna array, we proposed the lattice-like arrangement composite metasurface (LACMS). When EM waves normally illuminates on the metasurface, the scattering energy redistributes to the end-fire direction. Compared with the...
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