# Low Profile Dual-Band Polarization Conversion Metasurface with Omnidirectional Polarization

^{1}

^{2}

^{*}

^{†}

## Abstract

**:**

## 1. Introduction

## 2. Design and Analysis

#### 2.1. Design of PCM Element

_{au}and Y

_{bu}admittance are equivalent to the upper inner and outer metal patches, and the resonators with Y

_{al}and Y

_{bl}admittance are equivalent to the lower inner and outer patches, respectively. Y

_{au}can be expressed as:

_{bu}is calculated similarly to Y

_{au}. The equivalent circuit model of the PCM is symmetric with respect to the ground, since the lower metal patches are the same as the upper ones, only at different locations. The coaxial-via-hole connection can be equivalent to the inductance transmission (L

_{v}

_{1}and L

_{v}

_{2}), and the upper and lower resonators are connected in series. The transmission of the inner and outer patches from one end of the PCM to the other can be equivalent to two transmission paths. The transmission matrix of one of the paths can be written as [24]:

_{I}+ Y

_{II}of the equivalent circuit in Figure 3a can be obtained, and the cross-polarization transmission coefficient and co-polarization reflection coefficient can be further calculated as:

#### 2.2. Mechanism of PCM

## 3. Fabrication and Measurement

## 4. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## References

- Zhou, G.; Zhu, B.; Zhao, J.; Zhu, G.; Jin, B.; Feng, Y.; Kang, L.; Xu, W.; Chen, J.; Wu, P. A broadband reflective-type half-wave plate employing optical feedbacks. Sci. Rep.
**2017**, 7, 9103. [Google Scholar] [CrossRef] [Green Version] - Zheng, Q.; Guo, C.; Vandenbosch, G.A.; Yuan, P.; Ding, J. Dual-broadband highly efficient reflective multi-polarisation converter based on multi-order plasmon resonant metasurface. IET Microw. Antennas Propag.
**2020**, 14, 967–972. [Google Scholar] [CrossRef] - Benetou, M.I.; Tsakmakidis, K.L. Multifunctional plasmonic metasurface demultiplexer and wavelength-polarization controllable beam splitter. JOSA B
**2021**, 38, C50–C57. [Google Scholar] [CrossRef] - Aparna, U.; Mruthyunjaya, H.S.; Sathish Kumar, M. Plasmonic nanoslit-based dual-wavelength multiplexer. J. Opt.
**2020**, 49, 17–22. [Google Scholar] [CrossRef] - Kowerdziej, R.; Wróbel, J.; Kula, P. Ultrafast electrical switching of nanostructured metadevice with dual-frequency liquid crystal. Sci. Rep.
**2019**, 9, 20367. [Google Scholar] [CrossRef] [PubMed] [Green Version] - Amireddy, K.K.; Balasubramaniam, K.; Rajagopal, P. Holey-structured metamaterial lens for subwavelength resolution in ultrasonic characterization of metallic components. Appl. Phys. Lett.
**2016**, 108, 224101. [Google Scholar] [CrossRef] - Han, B.; Li, S.; Cao, X.; Han, J.; Jidi, L.; Li, Y. Dual-band transmissive metasurface with linear to dual-circular polarization conversion simultaneously. AIP Adv.
**2020**, 10, 125025. [Google Scholar] [CrossRef] - Fahad, A.K.; Ruan, C.; Nazir, R.; Haq, T.U.; He, W. Dual-band ultrathin meta-array for polarization conversion in Ku/Ka-band with broadband transmission. IEEE Antennas Wirel. Propag. Lett.
**2021**, 19, 856–860. [Google Scholar] [CrossRef] - Hoque, A.; Tariqul Islam, M.; Almutairi, A.F.; Alam, T.; Jit Singh, M.; Amin, N. A Polarization Independent Quasi-TEM Metamaterial Absorber for X and Ku Band Sensing Applications. Sensors
**2018**, 18, 4209. [Google Scholar] [CrossRef] [PubMed] [Green Version] - Fu, Y.; Cheng, H.; Wu, J.; Li, Y.; Dai, Y.; Wen, D.; Yang, H. A multifunctional metasurface with asymmetric transmission and high-efficiency cross-polarization converter. J. Appl. Phys.
**2022**, 132, 223106. [Google Scholar] [CrossRef] - Fei, P.; Guo, W.; Hu, W.; Zheng, Q.; Wen, X.; Chen, X.; Vandenbosch, G.A.E. A Transmissive Frequency-Reconfigurable Cross-Polarization Conversion Surface. IEEE Antennas Wirel. Propag. Lett.
**2022**, 21, 997–1001. [Google Scholar] [CrossRef] - Ako, R.T.; Lee, W.S.; Atakaramians, S.; Bhaskaran, M.; Sriram, S.; Withayachumnankul, W. Ultra-wideband tri-layer transmissive linear polarization converter for terahertz waves. APL Photonics
**2020**, 5, 046101. [Google Scholar] [CrossRef] [Green Version] - Hong, T.; Wang, S.; Liu, Z.; Gong, S. RCS Reduction and Gain Enhancement for the Circularly Polarized Array by Polarization Conversion Metasurface Coating. IEEE Antennas Wirel. Propag. Lett.
**2019**, 18, 167–171. [Google Scholar] [CrossRef] - Ye, Y.; He, S. 90° polarization rotator using a bilayered chiral metamaterial with giant optical activity. Appl. Phys. Lett.
**2010**, 96, 203501. [Google Scholar] [CrossRef] - Xu, P.; Jiang, W.X.; Wang, S.Y.; Cui, T.J. An Ultrathin Cross-Polarization Converter with Near Unity Efficiency for Transmitted Waves. IEEE Trans. Antennas Propag.
**2018**, 66, 4370–4373. [Google Scholar] [CrossRef] - Zhao, Y.-T.; Zhang, J.-J.; Wu, B. Low Profile Reflective Polarization Conversion Metasurface With High Frequency Selectivity. IEEE Trans. Antennas Propag.
**2022**, 70, 10614–10622. [Google Scholar] [CrossRef] - Xu, P.; Wang, S.-Y.; Geyi, W. A linear polarization converter with near unity efficiency in microwave regime. J. Appl. Phys.
**2017**, 121, 144502. [Google Scholar] [CrossRef] - Zhou, X.; Wu, J.; Yang, H.; Li, S.; Yang, Y.; Chen, J. A dual-broadband dual-function polarization converter based on reflective metasurface. J. Appl. Phys.
**2022**, 132, 133103. [Google Scholar] [CrossRef] - Zheng, Q.; Guo, C.; Ding, J.; Fei, P.; Vandenbosch, G.A.E. High-efficiency multi-band multi-polarization metasurface-based reflective converter with multiple plasmon resonances. J. Appl. Phys.
**2021**, 130, 193104. [Google Scholar] [CrossRef] - Wu, J.; Syed, M.A.S.; Qi, L.; Tao, X.; Yang, J.; Wen, L. A double-layer high-transmission terahertz linear-to-circular polarization converter. J. Appl. Phys.
**2022**, 132, 013103. [Google Scholar] [CrossRef] - Chen, W.; Yu, Y.; Mu, Q.; Campos, J.; Wang, Q.; Li, S.; Zhang, S.; Xuan, L. Super-broadband geometric phase devices based on circular polarization converter with mirror symmetry. Appl. Phys. Lett.
**2021**, 119, 101103. [Google Scholar] [CrossRef] - Lin, B.; Huang, W.; Lv, L.; Guo, J.; Wang, Z.; Zhu, R. Second-Order Polarization Rotating Frequency-Selective Surface. IEEE Trans. Antennas Propag.
**2021**, 69, 7976–7981. [Google Scholar] [CrossRef] - Baghel, A.K.; Kulkarni, S.S.; Nayak, S.K. Linear-to-cross-polarization transmission converter using ultrathin and smaller periodicity metasurface. IEEE Antennas Wirel. Propag. Lett.
**2019**, 18, 1433–1437. [Google Scholar] [CrossRef] - Pozar, D.M. Microwave Engineering; John Wiley & Sons: Hoboken, NJ, USA, 2011. [Google Scholar]
- Zheng, Q.; Guo, C.; Ding, J. Wideband metasurface-based reflective polarization converter for linear-to-linear and linear-to-circular polarization conversion. IEEE Antennas Wirel. Propag. Lett.
**2018**, 17, 1459–1463. [Google Scholar] [CrossRef] - Huang, X.; Yang, H.; Zhang, D.; Luo, Y. Ultrathin Dual-Band Metasurface Polarization Converter. IEEE Trans. Antennas Propag.
**2019**, 67, 4636–4641. [Google Scholar] [CrossRef]

**Figure 1.**The unit cell of the proposed dual-band PCM where the top layer is connected with the bottom layer by four coaxial via-holes. The geometric dimensions are as follows: ${h}_{1}$ = 0.035, ${h}_{2}$ = 2, $p$ = 16.5, ${l}_{1}$ = 9, ${w}_{1}$ = 0.8, ${l}_{2}$ = 13.2, ${w}_{2}$ = 2.8, and ${d}_{1}$ = 0.4, ${d}_{2}$ = 1.4 (unit: mm).

**Figure 2.**Cross-polarization transmission coefficient and co-polarization reflection coefficient: (

**a**) under x-polarized and y-polarized waves; (

**b**) when polarization azimuth φ varies from 0° to 45° under x-polarized wave; and (

**c**) when polarization azimuth φ varies from 0° to 45° under y-polarized wave.

**Figure 3.**(

**a**) Equivalent-circuit model of the proposed PCM (${C}_{\mathrm{d}1}$ = 9.55 pF, ${L}_{1}$ = 0.4419 nH, ${C}_{1}$ = 2.5324 pF, ${R}_{1}$ = 2772 Ω, ${Lv}_{1}$ = 0.16 nH, ${C}_{\mathrm{d}2}$ = 8.71 pF, ${L}_{2}$ = 0.6424 nH, ${C}_{2}$ = 2.3596 pF, ${R}_{2}$ = 3030 Ω, ${L}_{\mathrm{v}2}$ = 0.38 nH). (

**b**) Cross-polarization transmission coefficient and co-polarization reflection coefficient of the PCM are calculated by full-wave simulation and equivalent circuit model.

**Figure 4.**Electric field distribution on the top and bottom surfaces at (

**a**) 4.64 GHz and (

**b**) 5.37 GHz with y-polarized wave incident.

**Figure 5.**Surface current vector distribution of unit top and bottom at 4.64 GHz when (

**a**) φ = 0° and (

**b**) φ = 30°.

**Figure 6.**The PCM prototype and experimental set-up. (

**a**) Top view of the PCM. (

**b**) Experimental setup for co-polarization reflection coefficient and cross-polarization transmission coefficient.

Electric Cond. | Thermal Cond. |
---|---|

$5.96\times {10}^{7}$ [S/m] | 401 [W/K/m] |

Relative Permittivity | Loss Tangent |
---|---|

2.65 | 0.002 |

Ref. | Passband | PCR | Thickness (λ _{L}) | Insertion Loss (dB) | * OP |
---|---|---|---|---|---|

[14] | Dual | 90% | 0.13 | 0.37/0.2 | No (SP) |

[15] | Single | 90% | 0.0235 | 1.16 | No (SP) |

[22] | Single | 90% | 0.07 | 0.8 | No (DP) |

[25] | Dual | 88% | 0.12 | 1.94/1.2 | No (DP) |

[26] | Dual | 86% | 0.069 | 0.4/1.9 | No (DP) |

This work | Dual | 90% | 0.062 | 0.22/0.35 | Yes |

Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content. |

© 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).

## Share and Cite

**MDPI and ACS Style**

Zhang, J.-J.; Xu, W.-X.; Zhao, Y.-T.; Xie, H.-Y.; Zu, H.-R.; Wu, B.
Low Profile Dual-Band Polarization Conversion Metasurface with Omnidirectional Polarization. *Materials* **2023**, *16*, 4347.
https://doi.org/10.3390/ma16124347

**AMA Style**

Zhang J-J, Xu W-X, Zhao Y-T, Xie H-Y, Zu H-R, Wu B.
Low Profile Dual-Band Polarization Conversion Metasurface with Omnidirectional Polarization. *Materials*. 2023; 16(12):4347.
https://doi.org/10.3390/ma16124347

**Chicago/Turabian Style**

Zhang, Jun-Jie, Wei-Xi Xu, Yu-Tong Zhao, Han-Yu Xie, Hao-Ran Zu, and Bian Wu.
2023. "Low Profile Dual-Band Polarization Conversion Metasurface with Omnidirectional Polarization" *Materials* 16, no. 12: 4347.
https://doi.org/10.3390/ma16124347