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This paper presents a multifunctional reflective polarization converter based on a metasurface, tailored for efficient and versatile polarization and phase manipulation in the terahertz frequency range. The proposed design excels in polarization multiplexing by integrating multiple conversion functions across two frequency bands It achieves precise deflection for linearly polarized waves and efficient mutual conversion between right-handed and left-handed circularly polarized waves in the 1.13-1.97 THz range, and high-performance mutual conversion between linearly polarized and circularly polarized waves from 2.03 to 2.97 THz. The metasurface enables distinct polarization conversion effects across multiple frequency bands, showcasing exceptional multiplexing capabilities. Additionally, it exhibits P-B phase manipulation properties, achieving consistent and uniform phase modulation over the entire operational bandwidth. As a result, the metasurface demonstrates outstanding beam focusing performance and efficient generation of OAM beams across a wide frequency range. These combined functionalities, supported by comprehensive numerical simulations, underscore the metasurface's significant potential for advanced multiplexing applications in electronic countermeasures, satellite communications, and next-generation wireless systems.
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http://dx.doi.org/10.1364/OE.558549 | DOI Listing |
Biogeochemistry
September 2025
Department of Earth Sciences, Uppsala University, Uppsala, 75236 Sweden.
Unlabelled: Ocean surface gravity waves facilitate gas exchanges primarily in two ways: (1) the formation of bubbles during wave breaking increases the surface area available for gas exchange, promoting CO transfer, and (2) wave-current interaction processes alter the sea surface partial pressure of CO and gas solubility, consequently affecting the CO flux. This study tests these influences using a global ocean-ice-biogeochemistry model under preindustrial conditions. The simulation results indicate that both wave-current interaction processes and the sea-state-dependent gas transfer scheme-which explicitly accounts for bubble-mediated gas transfer velocity-influence the air-sea CO flux, with substantial spatial and seasonal variations.
View Article and Find Full Text PDFSci Rep
August 2025
Department of Basic and Applied Sciences for Engineering, Sapienza University of Rome, 00161, Rome, Italy.
This study explores the potential of Bloch surface waves (BSWs) at the interface of a finite one-dimensional photonic crystal (1D-PC) and vacuum, exploiting spectroscopic ellipsometry in a range that encompasses the mid-infrared (4000 cm to 200 cm). BSWs can be excited in both σ and π polarizations, which in the ellipsometric configuration can be detected at the same time, presenting distinct advantages for sensor applications targeting the growth of thin solid films and molecular monolayers, surface-adsorbed gas molecules, and liquid droplets. Compared to other sensing techniques exploiting mid-infrared vibrational absorption lines for chemical-specific sensitivity, like waveguides, nano-antenna arrays, metasurfaces, attenuated total reflectance (ATR) in crystals or in optical fibers, the present approach features high field enhancements, strong field confinement, and large quality factors of the resonances, all while relying on a rather simple and potentially low-cost configuration.
View Article and Find Full Text PDFNat Commun
August 2025
Department of Applied Physics and Physico-Informatics, Keio University, Yokohama, Japan.
In solids, the crystal field couples the electronic orbital degree of freedom to the lattice. This coupling suggests that an excitation of lattice dynamics could trigger the dynamics of orbital angular momentum of electrons, thereby generating orbital currents-a flow of electronic orbital angular momentum. However, the interplay between orbital currents and lattice dynamics has been elusive.
View Article and Find Full Text PDFUltrason Sonochem
September 2025
College of Food Science and Engineering, Northwest A & F University, China. Electronic address:
This work studied three physical modifications, including ultrasound (US), ball-milling (BM), and cold plasma (CP) on Flammulina velutipes soluble dietary fibres (FV-SDF) regarding the structural and functional properties. Interestingly, BM was indicated to cause the most changes in SDF molecular structures among three modifications, refining surface morphology, significantly decreasing molecular weight, and exposing polar functional groups. This contributed to the greatly modified solubility and decreased viscosity of FV-SDF treated by BM that exerted a strong shear force onto SDF.
View Article and Find Full Text PDFMicromachines (Basel)
July 2025
Research Center in Industrial Technologies CRTI, Cheraga, P.O. Box 64, Algiers 16014, Algeria.
The propagation of interface acoustic waves (IAWs) along rotated YX-LiNbO/SU-8/ZX-Si structures is theoretically investigated to identify the Y-rotation angles that support the efficient propagation of low-loss modes guided along the structure's interface. A three-dimensional finite element analysis was performed to simulate IAW propagation in the layered structure and to optimize design parameters, specifically the thicknesses of the platinum (Pt) interdigital transducers (IDTs) and the SU-8 adhesive layer. The simulations revealed the existence of two types of IAWs travelling at different velocities under specific Y-rotated cuts of the LiNbO half-space.
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