Broadband Vortex Beam Generation Using Multimode Pancharatnam–Berry Metasurface

Xu, He‐Xiu; Liu, Haiwen; Ling, Xiaohui; Sun, Yun-Ming; Fang, Yuan

doi:10.1109/tap.2017.2761548

Cited by 193 publications

(101 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this scenario, we use a single metasurface to generate twin OAM beams with l = ±2 for LHCP in yoz plane whereas twin OAM beams with l = ±1 for RHCP in xoz plane. We note that the coding sequences for excitations of different spins are totally different that cannot be realized by common coding metasurface, due to the fact that previous works only use bare geometric or propagation phase . In addition, maintaining stable performances of desired EM functionalities in an ultrawide frequency band is also a very challenging task for the existing coding metasurfaces …”

Section: Concept and Meta‐atom Designmentioning

confidence: 99%

“…However, such metasurfaces comprising subwavelength‐scaled birefringent phasers can only afford distinct wavefront manipulations built with orthogonal linear polarizations, leaving much potentials unexploited because circularly‐polarized waves are more favorable in applications such as satellite communication, biological sensing. For these reasons, geometric phases have been employed to impart spatial phase gradient for orthogonal spins, unlocking many new phenomena and fascinating meta‐devices such as spin Hall effect, meta‐lens, etc. Although the geometric phase metasurface can realize multiple functionalities by using field‐multiplexing techniques, the spatial phase modulations are exactly opposite for excitations of different spins.…”

Section: Introductionmentioning

confidence: 99%

“…Although the geometric phase metasurface can realize multiple functionalities by using field‐multiplexing techniques, the spatial phase modulations are exactly opposite for excitations of different spins. Macroscopically, the vortex beams with the opposite topology charges and spins are generated if the geometric phase imposed on the building blocks possesses a helical gradient . Therefore, the intrinsically correlated phase modulation of geometric phase imposes severe limitations on practical applications.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Ultrawideband Spin‐Decoupled Coding Metasurface for Independent Dual‐Channel Wavefront Tailoring

et al. 2020

View full text Add to dashboard Cite

Achieving distinct functionalities for electromagnetic (EM) waves with opposite handedness in a broad frequency range is highly desirable and essential for modern wireless communications and radar stealth. However, available functional meta‐devices still suffer from the issues of locked functionalities or spin‐decoupled properties but with limited bandwidth. Here, a spin‐decoupled coding metasurface is presented for achieving independently spin‐controlled functionalities with high efficiency in an ultrawide frequency band. By synthesizing the Jones matrix, it is predicted that two half‐wave plates with a phase difference of 90° can form a 1‐bit coding metasurface operating for orthogonal spins independently. As proofs of concept, two meta‐devices are implemented by the metasurface in the microwave region. The first meta‐device performs as a spin‐decoupled beam deflector while the second one shows an ability to generate spin‐decoupled multi‐beams carrying desired orbital angular momentums. Both of the designed meta‐devices can operate in the whole band of 7.5–18.5 GHz (with relative bandwidth of 80%), which, to the best knowledge, is so far the broadest bandwidth that can be achieved by spin‐decoupled metasurfaces. This may trigger interest and open opportunities for advanced functional meta‐devices in practical applications, for example, multichannel metasurface antennas, or multifunctional low‐scattering devices in microwave region.

show abstract

Section: Concept and Meta‐atom Designmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Ultrawideband Spin‐Decoupled Coding Metasurface for Independent Dual‐Channel Wavefront Tailoring

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Content may change prior to final publication. [42] and the single-layer metasurfaces with spatially rotated double arrow-shaped meta-atom [43]. Although they can generate the vortex beams with a considerable wide bandwidth, there still lack a reliable model to design these meta-atom structures.…”

mentioning

confidence: 99%

Ultrawideband Reflection-Type Metasurface for Generating Integer and Fractional Orbital Angular Momentum

Yang

Sun

Sha

2020

IEEE Trans. Antennas Propagat.

126

View full text Add to dashboard Cite

Vortex beams carrying orbital angular momentum are extensively studied owing to its potential to expand channel capacity of microwave and optical communication. By utilizing the Pancharatnam-Berry phase concept, an ultra-wideband single-layer metasurface is proposed to realize the conversion from incident plane waves to reflected vortex beams covering a considerable bandwidth from 6.75 to 21.85 GHz (>105%). An equivalent circuit model combined with broadband phase shift network is developed to effectively design the meta-atoms in metasurface. It is the first time to design wideband metasurfaces with the phase-based characteristics. To verify the proposed model, some deformed square loop meta-atoms are proposed to construct the metasurfaces with broadband OAM characteristic. Moreover, the vortex beams with the integer (l = −3), fractional (l = −1.5), and high-order (l = −10) OAM mode are generated respectively. Based on an OAM spectral analysis, the mode purity of the generated vortex waves is discussed in detail. The experimental results achieve a good agreement with those obtained from the simulation, thus proving the effectiveness and practicability of the proposed method.Index Terms-Orbital angular momentum (OAM), fractional OAM mode, ultra-wideband, metasurface, Pancharatnam-Berry phase (PB).

show abstract

“…Typically, metasurfaces are constructed of metal [5,6] or dielectric [7,8] metaatoms with delicately designed geometries and orientations to locally modulate the pro perties of the scattered EM wave. [16][17][18][19] In addition, the concept of meta surface has also been adopted in many other research areas, such as the elastic meta surfaces [20,21] and acoustic metasurfaces. [16][17][18][19] In addition, the concept of meta surface has also been adopted in many other research areas, such as the elastic meta surfaces [20,21] and acoustic metasurfaces.…”

mentioning

confidence: 99%

High‐Efficiency Ultrathin Dual‐Wavelength Pancharatnam–Berry Metasurfaces with Complete Independent Phase Control

Xie

Zhai

Wang

et al. 2019

Advanced Optical Materials

View full text Add to dashboard Cite

The research field of metamaterials has become one of the most important areas in the past two decades due to the meta materials' unconventional electromagnetic properties that do not readily exists in natural materials. A large number of inno vative applications based on metamaterials have been proposed and experimentally verified, such as negative refraction [1] and cloaking. [2] Unfortunately, the widespread applications of metamaterials have been severely limited due to the fabrication challenges and material losses.Metasurfaces [3,4] are 2D arrangement of subwavelength metaatoms (unit cells) engineered to manipulate the properties (e.g., phase, amplitude, and polarization) of the electromagnetic (EM) waves, which fea ture easy fabrication and reduced absorp tion loss compared to 3D meta materials. Typically, metasurfaces are constructed of metal [5,6] or dielectric [7,8] metaatoms with delicately designed geometries and orientations to locally modulate the pro perties of the scattered EM wave. Due to the unpre cedented abilities to manipulate the EM wavefronts, metasurfaces have attracted enormous interests in different parts of the frequency spectra, and enabled a lot of novel planar metadevices, such as ultrathin skin cloak, [9] metaholograms, [10] polarization con verters, [11] spin Hall effects, [12,13] metalenses, [14,15] and vortex beam generators. [16][17][18][19] In addition, the concept of meta surface has also been adopted in many other research areas, such as the elastic meta surfaces [20,21] and acoustic metasurfaces. [22,23] Although metasurfaces have been widely studied since their emergence, most metasurface devices are designed to operate at a single wavelength, and their function alters or the performance deteriorates as the wavelength is varied due to the dispersion nature. The wavelengthdependent behavior of the metasurfaces is one of the critical limitations in existing metasurface devices. Therefore, a number of investigations have been conducted to circumvent this limitation at two or more distinct wavelengths recently. [24][25][26][27][28][29][30][31][32][33] For instance, several multiwavelength devices are realized by grouping different sized resonators into a building block. [24,28,29,32] Another means for realizing multiwavelength metasurfaces is to interleave several functional sections com posed of particular resonators operating at one wavelength of the incident light. [27,31] However, the metasurface devices have Metasurfaces are planar structures that can offer unprecedented freedoms to manipulate electromagnetic wavefronts at deep-subwavelength scale. The wavelength-dependent behavior of the metasurface could severely reduce the design freedom. Besides, realizing high-efficiency metasurfaces with a simple design procedure and easy fabrication is of great interest. Here, a novel approach to design highly efficient meta-atoms that can achieve full 2π phase coverage at two wavelengths independently in the transmission mode is proposed. More specifically, a bilayer meta-atom is d...

show abstract

Broadband Vortex Beam Generation Using Multimode Pancharatnam–Berry Metasurface

Cited by 193 publications

References 36 publications

Ultrawideband Spin‐Decoupled Coding Metasurface for Independent Dual‐Channel Wavefront Tailoring

Ultrawideband Spin‐Decoupled Coding Metasurface for Independent Dual‐Channel Wavefront Tailoring

Ultrawideband Reflection-Type Metasurface for Generating Integer and Fractional Orbital Angular Momentum

High‐Efficiency Ultrathin Dual‐Wavelength Pancharatnam–Berry Metasurfaces with Complete Independent Phase Control

Contact Info

Product

Resources

About