Ultrathin Single Layer Metasurfaces with Ultra‐Wideband Operation for Both Transmission and Reflection

Abstract

Artificially engineered metasurfaces provide extraordinary wave control at the subwavelength scale. However, metasurfaces proposed so far suffer due to limited bandwidths. In this paper, extremely thin metasurfaces made of single metallic layer is experimentally presented for ultra‐wideband operation from 9.3 to 32.5 GHz (with a fractional band of 112%), working at both transmission and reflection modes simultaneously. The phase control is achieved by azimuthally rotating the scatterer based on Pancharatnam–Berry phase principle. Nearly uniform efficiency (≈25%), approaching the theoretical limit of the infinitely thin metasurface, is achieved throughout the operation band. Finally, the proposed design is implemented for applications, e.g., the generation of electromagnetic waves carrying orbital angular momentums as well as anomalous reflections and refractions. The metasurfaces are characterized numerically and experimentally and the results are in good agreements.

Dual-polarized multiplexed meta-holograms utilizing coding metasurface

“…Traditional holograms can be generated either by interference of a reference beam with the scattered beam from a real object, or by using numerical computation to calculate the phase information into surface structures [2][3][4]. Metasurfaces, composed of arrays of artificially designed planar subwavelength-scaled scatterers, are two-dimensional analogues of metamaterials [5][6][7][8][9][10]. Due to their extraordinary capability in tailoring wavefronts, numerous applications of metasurfaces have been proposed, such as anomalous reflectors/refractors [11,12], metalenses [13,14], orbital angular momentum (OAM) generators [15,16], metagratings [17,18] and multifunctional devices [19,20], to name a few.…”

Construction of a Cost-Effective Phased Array Through High-Efficiency Transmissive Programable Metasurface

“…Within microwave domain, metasurfaces also arouse a wide range of investigation, such as radiation improvement [5][6][7], perfect absorbers [8,9], OAM-EM wave generation [10][11][12][13], scattering reduction [14][15][16], holographic imaging [17,18], and energy harvesting [19]. Metasurfaces particularly demonstrate the unique abilities in waveform shaping through the phase manipulation of the building units in microwave metasurfaces.…”

Wide-Angle Circular Polarization Converter Based on a Metasurface of Z-Shaped Unit Cells

“…In recent years, various types of polarization converters based on metasurfaces have been successively proposed, including linear polarization (LP) to LP (that is 90 • polarization rotator) [3][4][5][6], LP to circular polarization (CP) [7][8][9], CP to CP (that is circular polarization rotation direction regulator) [10], and multiple conversion modes [11,12]. Great progress has been made in frequency band [13][14][15], bandwidth [16][17][18], volume [2], robustness [19,20], etc. However, most of the attention was focused on the LP converter, and the research on CP regulators is relatively few.…”