Frequency Reconfigurable and Multifunctional Metastructure Regulated by Nematic Liquid Crystal: Broadband Circular to Linear Polarization Converter

Abstract

With the tunability of the nematic liquid crystal (NLC), a broadband frequency reconfigurable and versatile metastructure (MS) is proposed and theoretically investigated in this paper, combining circular‐to‐linear (CTL) polarization conversion (PC) and circular‐to‐circular (CTC) PC simultaneously. The MS is composed of two via‐coupled modules, which can respond differently to the incident waves. Each module is connected utilizing a metal via a column, thus exceedingly enhancing the energy transmission and reducing the loss when transmitting. When the applied bias voltage (Vbias) is 0 V, the NCL molecules follow the initial orientation. The MS converts the incident right circular polarized (RCP) waves into linear polarized (LP) waves within 8.11–9.95 gigahertz (GHz) with a relative bandwidth of 20.38% and achieves the PC of left circular polarized (LCP) into RCP waves. As the Vbias reaches 20 V, the original operating interval reconfigures and shifts overall toward a lower frequency. The bandwidth of CTL is 7.66–9.02 GHz, and the CTC PC is broadened to 20.20%. Meanwhile, the structure justification is verified, and the inducing mechanism of PC is expounded. Possessing the merits of versatile collaborative processing and wide operating bands, such an MS is promising to be a polarization‐controlled application candidate and enrich multifunctional designs.

Switchable asymmetric transmission with broadband polarization conversion in vanadium dioxide-assisted terahertz metamaterials

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Effects of spot size on the operation mode of GaAs photoconductive semiconductor switch employing extrinsic photoconductivity

“…Gallium arsenide (GaAs) photoconductive semiconductor switch (PCSS) is a new type of solid-state device, that combines ultrafast laser with photoelectric semiconductor [1][2][3]. As one of the most promising high-power closing switches, it has drawn wide attention in the fields of highpower microwave generation and pulsed power technology, due to its many inherent advantages such as ultrafast switching, high power, low time jitter and compact structure [4][5][6].…”

Unveiling the Transformative Potential of SWCNT/In2O3 Heterostructures as High-Performance Catalysts for Overall Water Splitting

“…The excessive use of fossil fuels in various sectors, such as the automobile, space industry, and agriculture, has created enormous concerns about their depletion, which forced researchers to think of alternative clean energy sources to reduce the dependency on fossil fuels and create the way toward futuristic sustainable, eco-friendly, and emission-free energy sources . Hydrogen (H 2 ) energy is considered an immensely auspicious and sustainable energy source because of its emission-free nature, abundant raw source, and high energy density of ∼287 kJ mol –1 . , H 2 energy is extensively used for industrial purposes such as petroleum refining and synthesis of ammonia and methanol as well as exploring its vast market and competition in the futuristic fuel cell-based vehicles for transportation. , Among numerous approaches, electrocatalytic water splitting is the utmost exciting, facile, and practical pathway compared with other methods due to its low cost and high-purity generation of clean and green hydrogen energy and oxygen during hydrogen and oxygen evolution reactions. , However, it offers a large overpotential in alkaline medium, which limits the development of scalable hydrogen energy production, making it expensive due to the intake of high electric energy. , On the other hand, the energy-saving electrocatalyst can stimulate proton reduction reaction at low overpotentials and Tafel slopes with improved reaction kinetics. , Basically, the catalysts’ electrocatalytic performance exclusively depends on available active centers, the inherent properties of active centers, and mass transport properties . Therefore, it is extremely desirable to cultivate high-standard electrocatalysts that are bifunctional for hydrogen and oxygen generation with exclusive merits such as excellent electronic transport properties, exceptional intrinsic activities, inexpensive, highly available active centers, and high stability in an alkaline medium.…”

“…4,5 Among numerous approaches, electrocatalytic water splitting is the utmost exciting, facile, and practical pathway compared with other methods due to its low cost and high-purity generation of clean and green hydrogen energy and oxygen during hydrogen and oxygen evolution reactions. 6,7 However, it offers a large overpotential in alkaline medium, which limits the development of scalable hydrogen energy production, making it expensive due to the intake of high electric energy. 8,9 On the other hand, the energy-saving electrocatalyst can stimulate proton reduction reaction at low overpotentials and Tafel slopes with improved reaction kinetics.…”