All-dielectric integrated OAM meta-antenna in the 6G terahertz communication window

Abstract

The rapid development of 6G terahertz communication systems renders it critical to design low-cost and high-performance integrated antennas. Concurrently, orbital angular momentum (OAM), as an emerging physical dimension, shows immense potential in 6G communication and high-resolution imaging. Here, an all-dielectric integrated meta-antenna operating in the 6G terahertz communication window is demonstrated, which can generate a tightly focused vortex beam. By manipulating the propagation phase of terahertz waves, integrated meta-antennas with different topological charges are designed to generate vortex beams carrying OAM, which greatly enhances the design freedom of the antennas. Under physical size constraints, the design concept is demonstrated and experimentally validated at 0.14 THz. The integrated meta-antenna was fabricated using photocuring 3D printing technology. The electric field distributions of the meta-antennas carrying different topological charges are analyzed, and the experimental results show good agreement with the simulations. This work provides a general approach for designing compact and cost-efficient all-dielectric integrated meta-antennas capable of generating vortex beams, which offers broad prospects for applications in high-capacity 6G communication and high-resolution imaging.

Graphical abstract

Keywords

vortex beam / meta-antenna / all-dielectric / terahertz

1 Introduction

Terahertz waves are located between microwaves and infrared light in the electromagnetic spectrum, with a frequency range of 0.1 to 10 THz. Terahertz waves exhibit unique properties, including non-ionizing radiation, high penetration through many non-conducting materials, and broad spectral range [1]. These features have propelled the rapid development of terahertz technology in fields such as communications [2−4], imaging [5−7], sensing [8−10], and spectroscopic analysis [11−13]. Particularly, terahertz waves have gained significant attention in the 6G communication due to their extremely large bandwidth, which breaks through capacity bottlenecks and opens up a new paradigm of Integrated Sensing and Communication (ISAC) [14]. As terahertz technology advances toward 6G communication systems, higher demands are emerging for the performance of terahertz antennas. Exploring and developing high-performance integrated terahertz antennas is vital for the future development of 6G communication.

The emerging terahertz devices enable the precise control of the amplitude, polarization, phase, and orbital angular momentum of electromagnetic waves, offering a novel approach for designing functional terahertz antennas. Beams carrying OAM offer an additional degree of freedom for engineering terahertz waves. OAM vortex beams with different topological modes are mutually orthogonal, which enables mode-division multiplexing [15]. Serving as a candidate technology for 6G communications systems, this technology holds great potential for increasing the channel capacity and improving spectrum utilization [16−18]. On the other hand, the central amplitude of the vortex beam is zero, resulting in a doughnut-shaped intensity distribution, which can be applied in the field of high-resolution imaging [19−21]. Recently, various terahertz devices have been investigated for generating vortex beams, including spiral phase plates [22, 23], spatial light modulators [24, 25], and computational holography [26, 27]. Owing to the long wavelength of terahertz waves, conventional terahertz antennas suffer from large size, high cost, and low efficiency, hindering their further application. Metasurfaces can flexibly control the wavefront of terahertz waves at subwavelength scales, sparking significant interest in the research on terahertz devices [28−30]. Up to now, extensive research has been conducted on terahertz metasurfaces for generating vortex beams [31−35]. The inherent ohmic losses of metallic resonant metasurfaces degrade device performance, hindering their practical application. All-dielectric metasurfaces exhibit high transmission efficiency in the terahertz regime. This property makes them an ideal platform for various functional devices, such as focusing [36, 37], polarization conversion [38−41], holography [42, 43], and multifunctional multiplexing [44, 45]. However, commonly used silicon-based metasurfaces face challenges such as high costs, intricate nanofabrication requirements, and are more suitable for higher-frequency regimes. With the growing demand for high-efficiency, low-cost, and compact integrated systems, the integrated meta-antenna has become a major development goal. However, there are only considerably few studies about the all-dielectric meta-antenna operating in the 6G terahertz communication window. Developing OAM-based 6G meta-antennas is expected to bring new breakthroughs in high-speed, high-capacity wireless communication, high-resolution imaging, and secure communications.

Here, we present an all-dielectric meta-antenna for generating vortex beams, which operates in the 6G terahertz communication window. By precisely controlling the propagation phase, metasurfaces carrying OAM are designed and integrated with an antenna, producing a focused vortex beam at the focal plane. The design concept of the integrated meta-antenna is demonstrated with a physical size constraint. In simulations, each meta-atom achieves a high transmittance of 91% across the frequency band of interest. The electric field distributions of the meta-antennas with different topological charges are analyzed. The integrated meta-antenna was fabricated using photocuring 3D printing technology with UV-curable resin and experimentally validated at 0.14 THz. The experimental results agree well with the simulations, verifying the accuracy of the theoretical design. In addition, the design methodology can be extended to other frequency bands. This work provides a general approach for developing high-efficiency integrated OAM meta-antenna. Our design will offer new avenues for advances in 6G communication and high-resolution imaging.

2 Results and discussion

2.1 Principle and design

The excellent electromagnetic manipulation capabilities of phase-gradient metasurfaces offer a flexible approach to antenna design. In this paper, we design and fabricated an all-dielectric OAM antenna using UV-sensitive resin, which operates at 0.14 THz, corresponding to a wavelength of 2.14 mm. Figure 1(a) shows the schematic diagrams of the integrated all-dielectric meta-antenna, including flat-convex lens I, flat-convex lens II, horn antenna, and metalens. The combination of flat-convex lens I and flat-convex lens II in the horn antenna serves as a beam-expanding group, which ensures the normal incidence of terahertz waves and significantly enhances the beam focusing capability. The focal length, diameter, and thickness of the flat-convex lens I are F₁, D₁, and H₁, respectively, while the corresponding parameters of the flat-convex lens II are F₂, D₂, and H₂. The horn antenna is coupled to the terahertz source via a waveguide interface. The thickness of the lens is related to its focal length and other geometric parameters, which is expressed as [46]

(1)

where n is the refractive index of the UV-sensitive resin. The focal lengths match the specification of commercial terahertz sources, ensuring compatibility with existing systems. Meanwhile, to meet the spatial design constraints, the rear diameter of the horn antenna is matched to the diameter of flat-convex lens II. The length of the horn antenna is T. Table 1 shows the structural parameters of the designed meta-antenna.

As shown in the inset of Fig. 1(a), the metasurface is initially designed as a periodic array comprising 65 × 65 meta-atoms. To accommodate the requirements for system integration, the fabricated prototype is subsequently trimmed into a final circular aperture with a diameter of 52 mm. The length and width of the selected meta-atoms are P, and the height is H. The metasurface can effectively excite OAM beams at 0.14 THz. Theoretically, the phase change of the electromagnetic wave is caused by the phase accumulated along the propagation path by the meta-atoms, which can be expressed as [47]

(2)\phi =k_0\times n\times H,

where k₀ is the wave number in free space at 0.14 THz. The phase change depends on the height H of the meta-atoms. When the incident beam passes through the metasurface, a certain optical path difference is caused by the uneven height of the metasurface, resulting in a corresponding change in phase. As a result, the outgoing beam transforms into a vortex beam with a helical wavefront, as shown in the inset at the bottom left of Fig. 1(a). Wavefront phase modulation of incident electromagnetic waves requires that the phase difference covers a range of 2π, which can be realized by adjusting the height H of the meta-atoms. As shown in Fig. 1(b), increasing the height H of the meta-atoms from 0.1 mm to 1.4 mm achieves the desired phase of the metasurface. The scanning step size is set to 100 μm, determined by the precision of the 3D printing system. The meta-atoms achieve a high transmittance of 91% at 0.14 THz. The careful selection of the lattice period P is critical for achieving high-efficiency operation while suppressing anomalous scattering. Following established electromagnetic design principles and considering fabrication constraints of the 3D printer ELEGOO Saturn 3 Ultra, the period P is 0.8 mm. Simultaneously, the period is also chosen in relation to the overall physical dimensions of the antenna to ensure a feasible and functional device layout. Therefore, P = 0.8 mm represents a carefully selected parameter that reconciles wavefront engineering requirements with available fabrication technology and structural integration. As shown in Fig. 1(c), transmission phase shifts of the selected meta-atoms cover a range of 2π, achieving arbitrary wavefront manipulation from 0.1 THz to 0.28 THz. To generate the focused vortex beams carrying OAM, precise integration of two independent phase profiles is required, including the spiral phase distribution along the azimuthal direction and the focusing phase distribution along the radial direction. When the spiral phase and the focusing phase are superimposed, the phase distribution is expressed as [48]

(3){\varphi }_{\left(r,\theta \right)}=\pm {\displaystyle \frac{2\pi }{\lambda }}\left(f-\sqrt{r^2+f^2}\right)+l\times \theta ,

where λ denotes the operating wavelength corresponding to a frequency of 0.14 THz, f represents the focal length of the metasurface, which is set to 60 mm, r is the distance from the coordinate origin, θ is the azimuthal angle, l is the topological charge of the vortex wave, representing the number of 2π phase periods around the singularity. The meta-antenna is achieved by combining the focusing and the helical phases. The designed meta-antenna provides new degrees of freedom for the precise control and application of electromagnetic waves with its unique electromagnetic wave manipulation ability and OAM characteristics. Figure 1(d) shows the transmittance of selected meta-atoms from 0.1 THz to 0.28 THz. It can be seen that the variation of the period has little effect on the transmittance. Although an increase in the height of the meta-atom generally leads to a decrease in transmittance, the selected meta-atoms maintain high transmittance across 0.1 THz to 0.18 THz. This property contributes to designing high-performance meta-antenna.

2.2 Simulation and analysis

It is known that a vortex beam differs from an ordinary beam principally by an additional phase factor e^ilθ. This phase factor results in a helical wavefront propagating along the z-direction. By adding multiples of 2π to the radial phase variation, the incident Gaussian beam is transformed into a vortex beam. Vortex beams have potential applications in emerging fields such as high-resolution imaging, object detection, and optical devices.

To demonstrate the performance of the proposed meta-antenna, we employed CST Microwave Studio for full-wave electromagnetic simulations to optimize the geometric parameters of the meta-atoms and characterize the electromagnetic properties of the meta-antenna. In the simulation, the open boundary conditions are set in the x- and y-directions, and an open (add space) boundary condition is adopted along the z-direction. Additionally, the phase center of the meta-antenna is precisely aligned with the focal point of the metasurface to optimize aperture efficiency. The transmitted electric field intensity distributions of the metasurface with different topological charges (L = −1, +1, −2, and +2) are simulated by placing a field monitor on the focal plane. As presented in Fig. 2, the metasurface can generate vortices with different topological charges on the focal plane. The vortex beam exhibits a doughnut-shaped intensity distribution with a central singularity at z = 60 mm. Although the intensity distributions are non-uniform, the phase distributions for different topological charges are clearly observed. The radius of the ring is determined by the value of the topological charges L.

Taking the metasurface with topological charge L = +2 as an example, the propagation characteristics of the generated vortex beam are analyzed in detail. Figure 3(a) presents the axial electric field intensity distribution of the focused vortex beam. To observe the variation of the focused vortex beam along the z-axis, the electric field intensities and phase profiles are monitored at four observation x−y planes at distances of 40 mm, 50 mm, 60 mm, and 70 mm from the metasurface, as shown in Figs. 3(b) and (c). The corresponding normalized intensities are plotted and presented in Fig. 3(d). Near the focal plane, the electric field intensities of the OAM vortex beam are kept almost unchanged. Compared to the conventional vortex beam, the focused OAM vortex beam exhibits lower divergence. The FWHM of the focal spot is a key parameter for determining the spatial resolution and imaging quality of a lens. Generally, a smaller FWHM indicates a more concentrated energy distribution [49, 50]. The FWHM of the generated vortex beam with topological charge L = +2 is 2.09 mm at the focal plane (z = 60 mm). The proposed meta-antenna demonstrates excellent performance in efficiently generating and manipulating OAM vortex beams. This capability not only enables compatibility with 6G communication standards but also imparts novel functionalities to traditional antenna systems.

2.3 Fabrication

The 3D printing technology offers a versatile platform for fabricating complex meta-devices in the THz range. It presents a promising fabrication approach for manufacturing industrial-grade components essential for future 6G communication systems. To verify the proposed concept, the designed meta-antenna was fabricated by the commercial 3D printer (ELEGOO Saturn 3 Ultra) using UV-sensitive resin, as presented in Fig. 4(a). The UV-sensitive resin, characterized by terahertz time-domain spectroscopy (THz-TDS Advantest, TAS7500TS) at 0.14 THz, exhibits a refractive index of 1.644 with a loss tangent of approximately 0.0187. It is an excellent material to design the meta-antenna, which can balance the loss and manipulation performance. Figure 4(b) depicts the schematic diagram of LCD photocuring 3D printing technology. The UV-sensitive resin is cured via UV radiation. LCD-based stereolithography enables fabrication of complex 3D structures by high-speed curing and integrated molding, overcoming the geometric limitations inherent in subtractive manufacturing and thin-film techniques. As depicted in Figures 4(c)−(f), the fabricated meta-antenna assembly comprises a horn antenna, flat-convex lens I (D₁ = 14.96 mm), a metasurface (L = +2, D = 52.03 mm), and flat-convex lens II (D₂ = 50.05 mm). The dimensional errors of all components are measured to be within 50 μm. The fabricated metasurfaces with topological charges of L = +1, −1, and −2 are shown in Fig. 4(g). These metasurfaces are modularly interchangeable with the component illustrated in Fig. 4(e). The dimensional characterization of the fabricated metasurface (e.g., with L = +2) is performed using a calibrated digital vernier caliper. The statistical analysis in Fig. 4(h) presents the height variation of meta-atoms across 14 measurement points, confirming that the maximum geometric error is within the design specification of 100 μm, which ensures the required phase accuracy of the designed meta-antenna. Our design offers promising potential for applications in 6G communication, wireless power transfer, zoom imaging, and remote sensing

2.4 Characterization

To experimentally verify the focusing capabilities of the designed meta-antenna, the electric field distributions are measured utilizing a scanning detection system. As illustrated in Fig. 5(a), the measurement system consists of a terahertz source (Terasense Group, IMPATT Diodes, operating at 0.14 THz) and an ultrafast terahertz detector (Terasense Group, operating frequency: 0.05−0.70 THz). The meta-antenna is coupled to the terahertz source via a waveguide interface and is vertically illuminated by a 0.14 THz terahertz wave. The detector is placed at the focal plane to collect the corresponding electric field intensity information, with a scanning step size of 50 μm. Figure 5(b) displays the measured electric field intensity distributions at the focal plane for metasurfaces carrying different topological charges. The experimental results are in good agreement with the simulations. The electric field intensity distribution of the vortex beam at the focal plane exhibits a dark-hollow profile. The radius of the vortex beam increases with the absolute value of the topological charge. Figure 5(c) displays the electric field distribution in the x−z plane (y = 0) for the metasurface with a topological charge of L = +2. By translating the detector along the propagation path, the electric field intensities on the x−y plane at propagation distances of z = 40, 50, 60, and 70 mm are measured. The variation in the electric field of the focused vortex beam can be clearly observed in Fig. 5(d). The trend of the beam variation obtained from experiments is consistent with simulations. The corresponding normalized electric field intensity are presented in Fig. 5(e). The experimental FWHM of the focused vortex beam is inconsistent with the simulation. The 3D-printed metasurface unit structures are prone to dimensional deviations and surface roughness exceeding the standard, which will degrade the accuracy of phase modulation. And the performance of the detector limits the measurement resolution.The designed integrated meta-antenna effectively generates the focused vortex beam in the 6G terahertz communication windows, demonstrating its capability for beam control. Such versatility affords the meta-antenna considerable potential for diverse applications, including communication, imaging, processing, and quantum technologies.

3 Conclusion

We demonstrate a seamlessly integrated OAM meta-antenna operating in the 6G terahertz communication window. Metasurfaces carrying different OAM, designed through propagation phase manipulation, can be integrated with an all-dielectric antenna to generate focused vortex beams. The selected meta-atoms achieve a high transmittance of 91% at 0.14 THz. The simulated electric field intensities of the metasurface with different topological charges are monitored at the focal plane. The vortex beams carrying OAM are observed, exhibiting a doughnut-shaped intensity distribution. The designed integrated meta-antenna was fabricated using UV-curable resin via LCD photocuring 3D printing technology. Measurement results confirm that the designed meta-antenna generates distinct OAM modes by reconfiguring the metasurface. For the topological charge L = +2, the vortex beam evolution trends show excellent agreement between experiment and simulation. In conclusion, this study reports a generalized method for designing, optimizing, and fabricating high-efficiency integrated meta-antenna operating within the 6G terahertz communication window. Meanwhile, this method can be extended to other frequency bands. We believe our work holds great promise for high-resolution 6G terahertz spatial sensing, computational imaging, and multi-channel communication systems.

References

[1] M. Tonouchi , Cutting-edge terahertz technology, Nat. Photonics 1(2), 97 (2007)

[2] Y. Yang , Y. Yamagami , X. Yu , P. Pitchappa , J. Webber , B. Zhang , M. Fujita , T. Nagatsuma , and R. Singh , Terahertz topological photonics for on-chip communication, Nat. Photonics 14(7), 446 (2020)

[3] A. Kumar , M. Gupta , P. Pitchappa , N. Wang , P. Szriftgiser , G. Ducournau , and R. Singh , Phototunable chip-scale topological photonics: 160 Gbps waveguide and demultiplexer for THz 6G communication, Nat. Commun. 13(1), 5404 (2022)

[4] J. W. Zhou , Y. L. Yin , J. H. Tang , Y. Xia , and J. P. Yin , Information transmission through parallel multi-task-based recognition of high-resolution multiplexed orbital angular momentum, Front. Phys. (Beijing) 19(5), 52202 (2024)

[5] C. M. Watts , D. Shrekenhamer , J. Montoya , G. Lipworth , J. Hunt , T. Sleasman , S. Krishna , D. R. Smith , and W. J. Padilla , Terahertz compressive imaging with metamaterial spatial light modulators, Nat. Photonics 8(8), 605 (2014)

[6] R. I. Stantchev , B. Sun , S. M. Hornett , P. A. Hobson , G. M. Gibson , M. J. Padgett , and E. Hendry , Noninvasive, near-field terahertz imaging of hidden objects using a single-pixel detector, Sci. Adv. 2(6), e1600190 (2016)

[7] T. L. Cocker , V. Jelic , R. Hillenbrand , and F. A. Hegmann , Nanoscale terahertz scanning probe microscopy, Nat. Photonics 15(8), 558 (2021)

[8] Y. Z. Shi , S. Xiong , Y. Zhang , L. K. Chin , Y. Y. Chen , J. B. Zhang , T. H. Zhang , W. Ser , A. Larrson , S. H. Lim , J. H. Wu , T. N. Chen , Z. C. Yang , Y. L. Hao , B. Liedberg , P. H. Yap , K. Wang , D. P. Tsai , C. W. Qiu , and A. Q. Liu , Sculpting nanoparticle dynamics for single-bacteria-level screening and direct binding-efficiency measurement, Nat. Commun. 9(1), 815 (2018)

[9] A. Tittl , A. Leitis , M. Liu , F. Yesilkoy , D. Y. Choi , D. N. Neshev , Y. S. Kivshar , and H. Altug , Imaging-based molecular barcoding with pixelated dielectric metasurfaces, Science 360(6393), 1105 (2018)

[10] J. Li , X. G. Lu , H. Li , C. Y. Song , Q. Tan , Y. He , J. Y. Liu , L. Luo , T. T. Tang , T. T. Liu , H. Xu , S. Y. Xiao , W. X. Huang , Y. Shen , Y. Zhang , Y. T. Zhang , and J. Q. Yao , Racemic dielectric metasurfaces for arbitrary terahertz polarization rotation and wavefront manipulation, Opto-Electronic Adv. 7(10), 240075 (2024)

[11] M. Faraji-Dana , E. Arbabi , A. Arbabi , S. M. Kamali , H. Kwon , and A. Faraon , Compact folded metasurface spectrometer, Nat. Commun. 9(1), 4196 (2018)

[12] M. Faraji-Dana , E. Arbabi , H. Kwon , S. M. Kamali , A. Arbabi , J. G. Bartholomew , and A. Faraon , Hyperspectral imager with folded metasurface optics, ACS Photonics 6(8), 2161 (2019)

[13] Y. Z. Shi , Z. H. Ma , H. Y. Chen , Y. G. Ke , Y. Chen , and X. X. Zhou , High-resolution recognition of FOAM modes via an improved EfficientNet V2 based convolutional neural network, Front. Phys. (Beijing) 19(3), 32205 (2024)

[14] A. Liu,Z. Huang,M. Li,Y. Wan,W. Li,T. X. Han,C. Liu,R. Du,D. K. P. Tan,J. Lu,Y. Shen,F. Colone,K. Chetty, A survey on fundamental limits of integrated sensing and communication, IEEE Commun. Surv. Tutor. 24(2), 994 (2022)

[15] N. Bozinovic , Y. Yue , Y. Ren , M. Tur , P. Kristensen , H. Huang , A. E. Willner , and S. Ramachandran , Terabit-scale orbital angular momentum mode division multiplexing in fibers, Science 340(6140), 1545 (2013)

[16] X. Jiang,Y. Zhao,C. Zhang, Capacity evaluation on the long-distance orbital angular momentum non-orthogonal transmission, in: 2018 IEEE MTT-S International Wireless Symposium, 1 (2018)

[17] Y. Han , S. Ye , W. Wan , M. Xun , Y. He , Q. Gong , and Y. Li , Orbital angular momentum meta‐holography with full‐polarization control, Laser Photonics Rev. 2025, e01130 (2025)

[18] T. Lei , M. Zhang , Y. Li , P. Jia , G. N. Liu , X. Xu , Z. Li , C. Min , J. Lin , C. Yu , H. Niu , and X. Yuan , Massive individual orbital angular momentum channels for multiplexing enabled by Dammann gratings, Light Sci. Appl. 4(3), e257 (2015)

[19] Z. Xing , Z. Lin , N. Liu , H. Gao , Y. Hu , Z. Liu , Z. Jiang , X. Zhang , and C. Zhang , Monolithic spin‐multiplexing metalens for dual‐functional imaging, Laser Photonics Rev. 19(12), 2401993 (2025)

[20] C. Schlickriede , S. S. Kruk , L. Wang , B. Sain , Y. Kivshar , and T. Zentgraf , Nonlinear imaging with all-dielectric metasurfaces, Nano Lett. 20(6), 4370 (2020)

[21] R. J. Lin , V. C. Su , S. Wang , M. K. Chen , T. L. Chung , Y. H. Chen , H. Y. Kuo , J. W. Chen , J. Chen , Y. T. Huang , J. H. Wang , C. H. Chu , P. C. Wu , T. Li , Z. Wang , S. Zhu , and D. P. Tsai , Achromatic metalens array for full-colour light-field imaging, Nat. Nanotechnol. 14(3), 227 (2019)

[22] X. Hui , S. Zheng , Y. Hu , C. Xu , X. Jin , H. Chi , and X. Zhang , Ultralow reflectivity spiral phase plate for generation of millimeter-wave OAM beam, IEEE Antennas Wirel. Propag. Lett. 14, 966 (2015)

[23] Y. Chen,S. Zheng,Y. Li,X. Hui,X. Jin,H. Chi,X. Zhang, A flat-lensed spiral phase plate based on phase-shifting surface for generation of millimeter-wave OAM beam, IEEE Antennas Wirel. Propag. Lett. 15, 1156 (2016)

[24] C. Maurer , A. Jesacher , S. Fürhapter , S. Bernet , and M. Ritsch-Marte , Tailoring of arbitrary optical vector beams, New J. Phys. 9(3), 78 (2007)

[25] Z. Xie , X. Wang , J. Ye , S. Feng , W. Sun , T. Akalin , and Y. Zhang , Spatial terahertz modulator, Sci. Rep. 3(1), 3347 (2013)

[26] L. Marrucci , C. Manzo , and D. Paparo , Optical spin-to-orbital angular momentum conversion in inhomogeneous anisotropic media, Phys. Rev. Lett. 96(16), 163905 (2006)

[27] Z. Zeng and D. Zhao , Superposed Laguerre‐Gaussian beams‐based orbital angular momentum holography, Laser Photonics Rev. 18(5), 2300965 (2024)

[28] H. H. Gao , X. J. Huang , X. W. Ma , X. Y. Li , L. Y. Guo , and H. L. Yang , An ultra-wideband coding polarizer for beam control and RCS reduction, Front. Phys. (Beijing) 18(4), 42301 (2023)

[29] C. L. Zheng , P. N. Ni , Y. Y. Xie , and P. Genevet , On-chip light control of semiconductor optoelectronic devices using integrated metasurfaces, Opto-Electronic Adv. 8(1), 240159 (2025)

[30] Z. Zhao , Z. Y. Lin , J. L. Ding , J. Q. Yang , L. Luo , T. T. Tang , J. Li , and J. Yao , Efficient angular dispersions manipulation of terahertz metasurface based on extrinsic chirality, Opto-Electronic Eng. 52(8), 250093 (2025)

[31] S. J. Li , Z. Y. Li , G. S. Huang , X. B. Liu , R. Q. Li , and X. Y. Cao , Digital coding transmissive metasurface for multi-OAM-beam, Front. Phys. (Beijing) 17(6), 62501 (2022)

[32] L. W. Wu , H. F. Ma , Y. Gou , R. Y. Wu , Z. X. Wang , M. Wang , X. Gao , and T. J. Cui , High-Transmission ultrathin Huygens’ metasurface with 360° phase control by using double-layer transmitarray elements, Phys. Rev. Appl. 12(2), 024012 (2019)

[33] C. Zheng , J. Li , J. Liu , J. Li , Z. Yue , H. Li , F. Yang , Y. Zhang , Y. Zhang , and J. Yao , Creating longitudinally varying vector vortex beams with an all-dielectric metasurface, Laser Photonics Rev. 16(10), 2200236 (2022)

[34] Q. Zhou , M. Liu , W. Zhu , L. Chen , Y. Ren , H. J. Lezec , Y. Lu , A. Agrawal , and T. Xu , Generation of perfect vortex beams by dielectric geometric metasurface for visible light, Laser Photonics Rev. 15(12), 2100390 (2021)

[35] J. C. Zhang,G. B. Wu,M. K. Chen,X. Liu,K. F. Chan,D. P. Tsai,C. H. Chan, A 6G meta-device for 3D varifocal, Sci. Adv. 9(4), eadf8478 (2023)

[36] Z. T. Sun , B. J. Xu , B. R. Wu , X. G. Wang , and H. Ying , High efficiency focusing and vortex generator based on polarization-insensitive gallium nitride metasurface, Nanomaterials (Basel) 11(10), 2638 (2021)

[37] Y. Xu , J. Gu , Y. Gao , Q. Yang , W. Liu , Z. Yao , Q. Xu , J. Han , and W. Zhang , Broadband achromatic terahertz metalens constituted by Si-SiO₂-Si hybrid meta-atoms, Adv. Funct. Mater. 33(35), 2302821 (2023)

[38] J. Li , C. Zheng , J. Li , G. Wang , J. Liu , Z. Yue , X. Hao , Y. Yang , F. Li , T. Tang , Y. Zhang , Y. Zhang , and J. Q. Yao , Terahertz wavefront shaping with multi-channel polarization conversion based on all-dielectric metasurface, Photon. Res. 9(10), 1939 (2021)

[39] C. X. Cai , Y. F. Li , Y. Y. Zhou , and Q. Pan , Chiral metasurfaces enabling tunable spin selection for multidimensional images and beam splitting, Front. Phys. (Beijing) 20(6), 064203 (2025)

[40] T. Nan , H. Zhao , J. Guo , X. Wang , H. Tian , and Y. Zhang , Generation of structured light beams with polarization variation along arbitrary spatial trajectories using tri-layer metasurfaces, Opto-Electronic Sci. 3(5), 230052 (2024)

[41] S. H. Cui , X. J. Huang , C. Z. Sun , H. L. Yang , and X. Y. Li , Efficient generation of polarization multiplexed OAM using levitated metasurfaces, Front. Phys. (Beijing) 20(1), 012202 (2025)

[42] J. Jang , G. Y. Lee , J. Sung , and B. Lee , Independent multichannel wavefront modulation for angle multiplexed meta-holograms, Adv. Opt. Mater. 9(17), 2100678 (2021)

[43] G. Y. Lee , G. Yoon , S. Y. Lee , H. Yun , J. Cho , K. Lee , H. Kim , J. Rho , and B. Lee , Complete amplitude and phase control of light using broadband holographic metasurfaces, Nanoscale 10(9), 4237 (2018)

[44] H. Yang,S. Zheng,H. Zhang,T. He,N. Li,Z. Yang,Z. Lyu,Y. He,L. Zhang,X. Yu, A reflective metasurface for OAM and polarization multiplexing communication in the W-Band, IEEE Antennas Wirel. Propag. Lett. 23(3), 1124 (2024)

[45] Q. Mai , C. Wang , X. Wang , S. Cheng , M. Cheng , Y. He , J. Xiao , H. Ye , D. Fan , Y. Li , and S. Chen , Metasurface based optical orbital angular momentum multiplexing for 100 GHz radio over fiber communication, J. Lightwave Technol. 39(19), 6159 (2021)

[46] J. Shi , M. Li , L. Tang , X. Li , X. Jia , C. Guo , H. Bai , H. Ma , X. Wang , P. Niu , J. Weng , and J. Yao , All‐dielectric integrated meta‐antenna operating in 6G terahertz communication window, Small 20(18), 2308958 (2024)

[47] X. He , Y. Yang , L. Deng , S. F. Li , and Feng , Printed sub-terahertz all-dielectric lens for arbitrary manipulation of quasi-nondiffractive orbital angular momentum waves, ACS Appl. Mater. Interfaces 13(17), 20770 (2021)

[48] W. Li , T. Meng , L. Dong , L. Liu , J. Liu , and G. Zhao , High efficiency focusing vortex generation and multichannel multiplexing based on terahertz metasurfaces, Sci. Rep. 15(1), 7499 (2025)

[49] K. Ou , G. H. Li , T. X. Li , H. Yang , F. L. Yu , J. Chen , Z. Y. Zhao , G. T. Cao , X. S. Chen , and W. Lu , High efficiency focusing vortex generation and detection with polarization-insensitive dielectric metasurfaces, Nanoscale 10(40), 19154 (2018)

[50] A. Arbabi , Y. Horie , A. J. Ball , M. Bagheri , and A. Faraon , Subwavelength-thick lenses with high numerical apertures and large efficiency based on high-contrast transmit arrays, Nat. Commun. 6(1), 7069 (2015)

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