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In this paper, we investigate a novel efficient metasurface-based wideband cross-polarization converter. The device rotates the y-polarized electromagnetic (EM) wave into an x-polarized EM-wave for a wide range of wavelengths (9.8 GHz–18.9 GHz) and vice versa. The unit cell of the proposed converter is very small and consists of four metal/dielectric layers. The asymmetric resonators represent a solid base to allow higher conversion efficiencies, while the slightly varying magnetic and electric resonances between neighboring layers produce a broad operating frequency range. Furthermore, only additive manufacturing technology was used, which offers a low-cost and simple solution to produce the complicated multilayer device. Both measured and simulated results are in good agreement confirming the excellent performance. This study can help both the affordable design and fabrication of multilayer wideband polarization converters in the future. [ABSTRACT FROM AUTHOR]

Using density functional theory and generalized gradient approximation for exchange and correlation, we present theoretical analysis of the electronic structure of recently synthesized graphyne and its boron nitride analog (labeled as BN-yne). The former is composed of hexagonal carbon rings joined by C-chains, while the latter is composed of hexagonal BN rings joined by C-chains. We have explored the nature of bonding and energy band structure of these unique systems characterized by sp and sp2 bonding. Both graphyne and BN-yne are found to be direct bandgap semiconductors. The bandgap can be modulated by changing the size of hexagonal ring and the length of carbon chain, providing more flexibilities of energy band engineering for device applications. The present study sheds theoretical insight on better understanding of the properties of the novel carbon-based 2D structures beyond the graphene sheet. [ABSTRACT FROM AUTHOR]