An Angularly Stable Tri-band Reflective Cross-polarization Conversion Anisotropic Metamaterial

An Angularly Stable Tri-band Reflective Cross-polarization Conversion Anisotropic Metamaterial

A tri-band microwave cross-polarization conversion (CPC) metasurface is designed
and simulated. The metasurface consists of a split-ring-resonator (SRRs) with two splits placed within perpendicular sides of the SRR and designed on an FR4 dielectric substrate backed by a metallic ground plane. An efficient CPC, both for normal as well as for oblique incidence, is achieved. This multi-band polarization conversion results from multiple plasmonic resonances occurring at three neighboring frequencies. Owing to sub-wavelength unit cell size, thin dielectric substrate, and optimized structure of the SRR, the response of the metasurface is independent of the incidence angle of the incoming wave which makes it a potential candidate for many practical applications.

introduction

Control and manipulation of the polarization state of electromagnetic waves have always been of profound interest in the scientific communities due to their fundamental role in a wide range of applications including contrast imaging microscopy, optical sensing, molecular biotechnology, and microwave communication. Although, the polarization of the electromagnetic waves can be manipulated through conventional methods such as the optical activity of the crystals and the Faraday Effect, however, such methods require bulky volume and are effective only for very narrow bandwidth. To control and manipulate the polarization of EM waves over a wide bandwidth and small distances, different metasurface-based designs have been proposed in the literature [1]. Polarization conversion metasurface designs usually consist of a two-dimensional periodic array of bi-anisotropic metallic elements placed over some dielectric. Polarization conversion has been achieved over different frequency ranges of the electromagnetic spectrum through different element geometries such as through plasmonic nano-rods in the visible regime [2], circular split rings in the infrared [3], metallic grating at terahertz [4], and self-complementary rings [5], rectangular loops with diagonal microstrips [6] and double-head-arrow structure [7] in the microwave regime. In this paper, a tri-band microwave cross-polarization-conversion (CPC) metasurface is designed and simulated. The metasurface consists of a two-dimensional periodic array of anisotropic split-ring-resonators (SRRs) designed on top of FR4 dielectric substrate backed by a metallic ground plane. The designed metasurface achieves triband cross-polarization conversion not only for normal but also for oblique incidence. Owing to sub-wavelength unit cell size, small dielectric thickness and overall optimized design of the unit cell, the response of the metasurface is independent of the incidence angle of the incoming wave which makes it a potential candidate for many practical applications.

To Download the paper click on the link bellow

https://doi.org/10.1063/1.4997456

To download the cst simulation file click on the  bellow🔽🔽🔽🔽🔽🔽

ꜜꜜꜜꜜ

https://drive.google.com/file/d/1tMcGb4g6ECwdkdprZz46DDB3UqZWgaks/view?usp=sharing

References

1.      Khan, M. I., Q. Fraz, and F. A. Tahir, “Ultra-wideband cross polarization conversion metasurface insensitive to incidence angle,” Journal of Applied Physics, Vol. 121, No. 4, 045103,
2017.

2.      . Zhao, Y. and A. Al`u, “Tailoring the dispersion of plasmonic nanorods to realize broadband
optical meta-waveplates,” Nano letters, Vol. 13, No. 3, 1086–1091, 2013.

3.      . Sieber, P. E. and D. H. Werner, “Reconfigurable broadband infrared circularly polarizing
reflectors based on phase changing birefringent metasurfaces,” Optics Express, Vol. 21, No. 1,
1087–1100 , 2013.

4.      . Grady, N. K., J. E. Heyes, D. R. Chowdhury, Y. Zeng, M. T. Reiten, A. K. Azad, A. J. Taylor,
D. A. Dalvit, and H. T. Chen, “Terahertz metamaterials for linear polarization conversion and
anomalous refraction,” Science, Vol. 340, No. 6138, 2013.

5.      . Wu, L., M. Zhang, B. Zhu, J. Zhao, T. Jiang, and Y. Feng, “Dualband asymmetric electromagnetic wave transmission for dual polarizations in chiral metamaterial structure,” Applied
Physics B, Vol. 117, No. 2, 527–531, 2014.

6.      . Zhu, H. L., S. W. Cheung, K. L. Chung, and T. I. Yuk, “Linearto-circular polarization conversion using metasurface,” IEEE Transactions on Antennas and Propagation, Vol. 61, No. 9,
4615–4623, 2013.

7.      . Kundu, D., A. Mohan, and A. Chakrabarty, “Ultrathin high-efficiency X-band reflective polarization converter using sunken double arrowhead metasurface,” 2016 Asia-Pacific Microwave
Conference (APMC), 1–4, IEEE, December 2016.