Shaping 3D Path of Electromagnetic Waves Using Gradient‐Refractive‐Index Metamaterials

Jiang, Wei; Ge, Shuo; Han, Tiancheng; Zhang, Shuang; Mehmood, Muhammad Qasim; Qiu, Cheng‐Wei; Cui, Tie Jun

doi:10.1002/advs.201600022

Cited by 27 publications

(23 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Figure 3d presents metalenses with an NA of 0.8 and efficiencies as high as 86% at visible wavelengths. [112] Stimulated by multiple applications, various metalenses have been proposed in recent years, such as multifocal metalenses, [113,114] 3D metalenses, [115] metalens doublets, [116,117] and Fourier metalenses. Diffraction-limited focusing and subwavelength resolution imaging are achieved with image qualities comparable to that of a state-of-the-art commercial objective lens.…”

Section: Metalensesmentioning

confidence: 99%

Phase Manipulation of Electromagnetic Waves with Metasurfaces and Its Applications in Nanophotonics

Chen

Zhang

et al. 2018

Advanced Optical Materials

121

View full text Add to dashboard Cite

elements. Thus, realizing phase manipulation of EM waves at the nanoscale has become a key pursuit for the development of modern optics and nanophotonics.Metamaterials are 3D artificial nanostructures composed of periodic subwavelength unit cells that resonantly couple to the incident EM waves, exhibiting effective electric and magnetic responses not found in nature. [1][2][3] However, these promising potential applications are hindered in their applications due to the challenges of fabricating the required complex 3D nanostructures and the inherent metallic losses and strong dispersion of plasmonic elements at optical frequencies. Planar metamaterials, or so-called metasurfaces, can be fabricated using existing technologies, such as the lithography method and have attracted increasing attention due to their feasibility, low loss, and ease of fabrication. [4,5] The most prominent advantage of metasurfaces is that they can generate spatial phase discontinuities over the full 2π range with an optically thin interface; moreover, the resolution is less than one wavelength. Thus, wavefronts can be shaped with a distance of much less than the wavelength. With the increasing development of metasurfaces, the aforementioned limitations can be solved using various ultrathin optical devices, which have properties superior to their conventional counterparts. [6][7][8][9][10][11][12] Here, we concentrate on the new capabilities of metasurfaces in recent years in manipulating the phase and propagation behaviors of EM waves. In Section 2, we briefly introduce the underlying mechanisms of three types of phase discontinuities. In Section 3, we review the basic applications of phase modulation using metasurfaces. In Section 4, we review more complex and advanced information photonics that have emerged from metasurfaces. In the last section, we provide concluding remarks and an outlook on future development directions. Three Basic Types of Phase Discontinuities Generated by Metasurfaces Resonance PhaseThe pioneering approach to achieve phase discontinuities was to use the dispersion of various metallic nanoantennas, as shown in the left panel of Figure 1a. The optical energy is coupled to surface EM waves propagating back and forth along the antenna surface. Due to the localized surface plasmon resonance, these waves are accompanied by oscillating free electrons Relative to conventional phase-modulation optical elements, metasurfaces (i.e., 2D versions of metamaterials) have shown novel optical phenomena and promising functionalities with more compact platforms and more straightforward fabrication processes. With the ability to generate a spatial phase variation, optical wavefronts can be manipulated into arbitrary shapes at will, enabling new phenomena and integrated ultrathin optical devices to be explored. This review is focused on recent developments regarding phase manipulation of electromagnetic waves with metasurfaces. Starting from their underlying physics for realizing full 2π phase manipulation, an overview of the applica...

show abstract

Section: Metalensesmentioning

confidence: 99%

Phase Manipulation of Electromagnetic Waves with Metasurfaces and Its Applications in Nanophotonics

Chen

Zhang

et al. 2018

Advanced Optical Materials

121

View full text Add to dashboard Cite

show abstract

“…The 2D immersion lens was later extended to 3D cases by the same group . The required distribution of relative permittivity of the 3D immersion lens is depicted in Figure a, which is obtained based on a similar TO procedure.…”

Section: Bulk Metamaterialsmentioning

confidence: 99%

“…Furthermore, based on the theory of TO and geometric optics (GO), metamaterials with specific spatial distribution of electromagnetic parameters provide a potent and powerful tool to control the propagation of EM waves, leading to many interesting physical phenomena . Various metamaterial‐based devices have emerged, such as invisible cloaks, optical illusion devices, anisotropic MTMs to control the polarization of EM waves, MTMs absorbers, ferrite‐based MTMs, TO lenses, and gradient‐refractive‐index (GRIN) lens antennas, which revealed the great potential of metamaterials in the future. In this way, a new era has been opened for metamaterials…”

Section: Introductionmentioning

confidence: 99%

Microwave Metamaterials

Chen

Tang

et al. 2019

Annalen der Physik

Self Cite

View full text Add to dashboard Cite

Metamaterials (MTMs) are artificial materials composed of subwavelength particles, which are engineered to achieve various electromagnetic (EM) responses. Since the first practical realization and experimental verification of MTMs by Pendry et al. in the late 1990s, great efforts have been made in theoretical study as well as practical utilizations. Among them, the effective medium theory provides a basis for the description as well as an accurate method for the design of MTMs, and leads to the development of many novel devices with interesting functionalities. With the employment of transformation and geometric optics, more high-performance engineering applications have been realized using MTMs. Recently, the concept of metasurfaces has been proposed, which further promotes the practical applications of advanced MTMs. Herein, the effective medium theory is first introduced. After that, typical devices and applications based on conventional bulk MTMs and newly-conceived metasurfaces are summarized to demonstrate the flexible capability of microwave MTMs in the manipulation of EM waves.Metamaterials are different from other periodic structures such as photonic crystals and frequency-selective surfaces (FSSs) because their unit cells are much smaller than the free-space wavelength. The subwavelength nature enables the metamaterials to Tianyi Chen received his B.Sc. degree from Southeast University, Nanjing, China, in 2013. He is currently working toward a Ph.D. degree in State Key Laboratory of Millimeter Waves at Southeast University. His research interests include metamaterials metasurfaces and antenna arrays. Wenxuan Tang received her B.Sc. and M.Sc. degrees from Southeast University, Nanjing, China, in Cheung-Kong Professor. His research interests include metamaterials, plasmonics in microwave, and computational electromagnetics.be treated as a homogenous effective medium and characterized by effective constitutive parameters. In early researches, closed formed expressions for the constitutive parameters were obtained in static and quasistatic limits, [86][87][88] which usually takes the form of Lorentz-Drude models. These results provided some intuition of the physical features but cannot quantitatively characterize metamaterials. In ref.[18], a numerical approach based on scattering (S) parameter retrieval was proposed to obtain the effective permittivity and permeability for periodic metamaterial structures. This method is accurate in the derivation of effective parameters. However it relies on full-wave simulation of metamaterial structures and hence is inefficient and difficult to be used in the design of large-volume metamaterials.In 2007, a general effective medium theory [17] was proposed by Liu et al., which sets up a relationship between particle responses and macroscopic behaviors of metamaterials. A closed form expression was provided to modify the Lorentz-Drude model, which takes the effects of spatial dispersion into account

show abstract

“…1(b), blue region) is applied to minimize the reflections. The resultant gradient refractive index can be implemented using alldielectric metamaterials by graded photonic crystals [36], or by drilling radial holes into the dielectric materials [37,38]. However, by considering the wavelength of the beam, the diameter of the holes needs to be in the range of tens to hundreds of nanometers.…”

Section: Design Of the Devicementioning

confidence: 99%

Long-range optical pulling force device based on vortex beams and transformation optics

Firuzi

Gong

2019

J. Opt.

View full text Add to dashboard Cite

In this work a method for generating a long-range optical pulling force is presented which is realized by utilizing a vortex beam and a device designed based on transformation optics through conformal mapping. The device works by transforming an input perfect vortex beam into an almost non-paraxial plane wave, and generates a pulling force by maximizing the forward momentum of the beam. A three-dimensional full-wave analysis of the device is performed and the optical force is computed by the Maxwell stress tensor method. The simulation results show a very good agreement with the theoretical calculations. *

show abstract

Shaping 3D Path of Electromagnetic Waves Using Gradient‐Refractive‐Index Metamaterials

Cited by 27 publications

References 22 publications

Phase Manipulation of Electromagnetic Waves with Metasurfaces and Its Applications in Nanophotonics

Phase Manipulation of Electromagnetic Waves with Metasurfaces and Its Applications in Nanophotonics

Microwave Metamaterials

Long-range optical pulling force device based on vortex beams and transformation optics

Contact Info

Product

Resources

About