Retrodirective metasurfaces from non-reciprocal to reciprocal using impedance modulation for high-super-cell-periodicity
- PDF / 1,246,285 Bytes
- 7 Pages / 595.276 x 790.866 pts Page_size
- 46 Downloads / 195 Views
Retrodirective metasurfaces from non‑reciprocal to reciprocal using impedance modulation for high‑super‑cell‑periodicity designs Mohammed Kalaagi1,2 · Divitha Seetharamdoo1,2 Received: 29 January 2020 / Accepted: 6 March 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract The growing popularity of metasurfaces and their exceptional physical phenomena has gained remarkable interest in terms of propagation and electromagnetic wave control. Particularly, for the case of retroreflection, retrodirective gradient metasurfaces are well known for their reciprocal responses in terms of retroreflection specially for subwavelength super-cell periodicity designs. Recently, we have observed that for metasurfaces with high super-cell periodicities greater than 2𝜆 , the retrodirective metasurface loses its reciprocal response in terms of retrodirectivity. The main challenge in this case is to retain the reciprocal response, as well as achieving efficient responses for retroreflection at the higher orders of diffraction that exist at these periodicities. Thus, in this paper we demonstrate the design of a retrodirective metasurface from non-reciprocal to reciprocal following the generalized phase law of reflection and introducing the impedance modulation technique, for a metasurface operating at 14.7 GHz with a super-cell periodicity of 2.88𝜆 . On the other hand, with a well-engineered surface impedance of a super-cell at these periodicities, efficient responses of retroreflection can be achieved at the higher orders of diffraction, giving rise to a retrodirective metasurface design operating simultaneously for multiple incident angles. Retroreflection has been achieved at eleven angles simultaneously, and the reciprocal property was retained at the desired angle of incidence 10◦. Keywords Metasurfaces · Retroreflection · Multiple angles · Surface impedance modulation · High-super-cell-periodicity designs
1 Introduction Metasurfaces [1, 2] have gained significant interest for their potential to manipulate the propagation of an electromagnetic wave in unconventional ways [3, 4]. Many functional designs have been developed based on metasurfaces for different applications in terms of electromagnetic wave control, which include beam steering [5–7] as well as the transformation of propagating waves into surface waves [8], multi-functional metasurfaces [9], polarization control [10], hologram [11], at microwave and optical frequencies. Different metasurface designs have also been introduced for dual * Mohammed Kalaagi [email protected] Divitha Seetharamdoo [email protected] 1
IFSTTAR, COSYS, LEOST, University of Lille 1 Nord de France, Lille, France
Institut de Recherche Technologique Railenium, 59650 Villeneuve d’Ascq, France
2
polarization applications [12–14], as well as for broad band frequency designs [15–17]. In the context of wave manipulation and control based on metasurface designs, retrodirective metasurfaces [12] have been shown to be an interesting feature for diff
Data Loading...
