Results 61 to 70 of about 2,524 (232)

Frequency-Reconfigurable Antenna Using Metasurface

open access: yesIEEE Transactions on Antennas and Propagation, 2014
A frequency-reconfigurable antenna designed using metasurface (MS) to operate at around 5 GHz is proposed and studied. The frequency-reconfigurable metasurfaced (FRMS) antenna is composed of a simple circular patch antenna and a circular MS with the same diameter of 40 mm (0.67 λ) and implemented using planar technology.
Zhu, HL, Liu, XH, Yuk, TTI, Cheung, SW
openaire   +3 more sources

Ti3C2Tx MXene/Silver Composite Foams For Lightweight, High‐Performance Electromagnetic Interference Shielding and Joule Heating

open access: yesAdvanced Materials Interfaces, EarlyView.
Ultrathin MXene/EMF composite foams achieve a specific shielding efficiency of 749.6 dB.dB·cm3$\mathrm{dB}\cdot {\mathrm{cm}}^{3}$/g, while the silver‐enhanced MXene/Ag/EMF reaches 81.4 dB shielding effectiveness at just 1.0 mm thickness. Both composites exhibit rapid Joule heating, retain stability up to 250∘C$^\circ{\rm C}$, and withstand 1000 ...
Abdullah A. Mahmood   +7 more
wiley   +1 more source

Transducers Across Scales and Frequencies: A System‐Level Framework for Multiphysics Integration and Co‐Design

open access: yesAdvanced Materials Technologies, EarlyView.
Transducers convert physical signals into electrical and optical representations, yet each mechanism is bounded by intrinsic trade‐offs across bandwidth, sensitivity, speed, and energy. This review maps transduction mechanisms across physical scale and frequency, showing how heterogeneous integration and multiphysics co‐design transform isolated ...
Aolei Xu   +8 more
wiley   +1 more source

Tunable Extraordinary Optical Transmission in the Long‐Wavelength Infrared Range Using Electrostatic MEMS Actuation

open access: yesAdvanced Materials Technologies, EarlyView.
A MEMS‐integrated metamaterial filter enables continuous, low‐voltage spectral tuning in the long‐wavelength infrared (LWIR). The device employs extraordinary optical transmission in a dual suspended metasurface stack, where electrostatic actuation precisely controls the intermembrane air gap.
Oleg Bannik   +6 more
wiley   +1 more source

Coupling of Er3+ ions and Plasmonic Modes in Vertical Nanocavities for Spectral Broadening in Telecom Bands

open access: yesAdvanced Materials Technologies, EarlyView.
Left: Illustration of the glass & nanostructures system and the NIR emission at 1.5 µm, where the colored spheres represent the Er3+ ions within the doped glass. Right: Representation of the Stark splitting of the 4I13/2 and 4I15/2 manifolds of the Er3+, illustrating how the plasmonic modes facilitate the emission from the broader Stark manifold ...
Gaston Lozano Calderón   +5 more
wiley   +1 more source

Spacer‐Less Substrate‐Integrated Metasurface for Near‐Unity Terahertz Absorption

open access: yesAdvanced Optical Materials, EarlyView.
ABSTRACT Although conventional metal‐insulator‐metal (MIM) terahertz (THz) absorbers can provide near‐unity absorption, their multilayer stacks inevitably introduce additional thickness, mass, and residual stress, which limit their compatibility with THz thermal sensing platforms.
Zihao Zhao   +6 more
wiley   +1 more source

A Wideband Quad-Polarization Reconfigurable Metasurface Antenna

open access: yesIEEE Access, 2018
A low-profile wideband metasurface antenna with quad-polarization reconfiguration ability is presented in this paper. The proposed metasurface antenna is composed of a square patch, a metasurface formed by a lattice of 4 × 4 periodic metal plates,
Jun Hu, Guo Qing Luo, Zhang-Cheng Hao
doaj   +1 more source

Revealing the Transmission Hologram's Refractive Index Profile Stored in a Photohydrogel: A Structural Characterization

open access: yesAdvanced Optical Materials, EarlyView.
A theoretical model is developed to visualize three‐dimensional refractive index profiles in transmission holographic gratings. In this work, it is applied to photopolymerizable hydrogels, enabling detailed analysis of the internal structure of recorded holograms and their evolution under different degradation conditions.
Belén Nieto‐Rodríguez   +4 more
wiley   +1 more source

Chip‐Integrated Metasurface‐GaAsSb Nanowire Array Photodetectors for Single‐Pixel Polarimetric Imaging

open access: yesAdvanced Optical Materials, EarlyView.
A 2×2 multiplexed GaAsSb nanowire photodetector array integrated with L‐shaped metasurfaces is developed for miniaturized infrared polarimetry. Leveraging non‐radiating anapole states that facilitate near‐field enhancement, the device demonstrates strong polarization selectivity at 835 nm.
Longsibo Huang   +14 more
wiley   +1 more source

Machine Learning Enables Inverse Design of Optically Driven Microscopic Metavehicles

open access: yesAdvanced Optical Materials, EarlyView.
Machine‐learning‐based inverse design is used optimize “metavehicles” — flat microparticles based on metagratings that generate a strong lateral optical force from normally incident light. The optimized design exhibits a force efficiency of ∼88% and a measured propulsion speed in water much higher than previously reported, demonstrating that inverse ...
Vasilii Mylnikov   +2 more
wiley   +1 more source

Home - About - Disclaimer - Privacy