Results 91 to 100 of about 141,223 (264)
Trajectory Planning and User Grouping for NOMA-Assisted UAV Data Collection
In this work, we investigate a NOMA based data collection system for UAVs. Our goal is to minimize the collection task completion time by considering UAV’s 3D trajectory and user grouping.
Guoxin Li +7 more
doaj +1 more source
Electrohydrodynamically Driven Broadband and Color‐Shifting in Cholesteric Liquid Crystals
Ion‐driven electrohydrodynamic effects enable dynamic photonic bandgap modulation in cholesteric liquid crystals under low‐frequency AC driving. By regulating ion‐mediated disturbance of the helical structure, this approach produces two reversible optical responses: rapid color shifting across the visible spectrum and broadband reflection spanning the ...
Cheng‐Kuan Wu +6 more
wiley +1 more source
An Improved Crayfish Algorithm-Based Neural Network Method for Modeling Microstrip Patch Antennas
Artificial neural networks (ANNs) have shown remarkable advantages in antenna modeling and optimization as surrogate models. However, in single-objective modeling, the convergence accuracy of ANN-based antenna models is often insufficient.
Shao-Long Cao +4 more
doaj +1 more source
Quantum Key Distribution for Optical Satellite Communications: An Engineering-Oriented Review
Satellite quantum key distribution (SatQKD) is widely regarded as a promising approach for extending quantum-secure key establishment beyond the distance limitations of terrestrial optical fiber links.
A. Popescu, A.-M. Badescu
doaj +1 more source
Flexible and Scalable 2D/3D Tin‐Based Perovskite Photodetectors via Inkjet Printing
Lead‐free tin‐based perovskite films are successfully fabricated via scalable inkjet printing on rigid and flexible substrates. Incorporating high‐purity precursors and dual‐layer encapsulation minimizes defects and eliminates oxidation. The resulting photodetectors demonstrate high responsivity, persistent photoconductivity, and excellent 30 day ...
Giovanni Vescio +13 more
wiley +1 more source
Energy transfer from broadband Bi3+ sensitizers to Eu3+ emitters enables composition‐, excitation‐, and temperature‐dependent luminescence in Na3Ca2TaO6. These controllable optical states support ratiometric thermometry and excitation‐selective, filter‐assisted information decoding in flexible phosphor–polydimethylsiloxane films, demonstrating how ...
Weiwei Xiang, Yuxiang Li, Jae Su Yu
wiley +1 more source
The epsilon‐near‐zero (ENZ) effect in metals emerges only in nanometer‐scale films with exceptional optical quality. Titanium nitride (TiN) films grown by molecular beam epitaxy retain high crystallinity down to 2 nm and exhibit dramatically enhanced nonlinear optical responses near the ENZ region.
Fan‐Ting Tseng +5 more
wiley +1 more source
Nanopatterned Dual‐Carbon‐Dot Photonic Films With Enhanced Light Outcoupling
Nanoimprinted dual‐carbon‐dot/PVA films combine composition‐tunable blue–green emission with grating‐mediated directional light outcoupling. Water‐processable B‐CD and G‐CD composites are patterned by drying‐assisted nanoimprinting, producing angle‐selective emission peaks that follow the first‐order diffraction condition and exhibit reference ...
Gyudam Jeon +3 more
wiley +1 more source
Cascading Spin‐Orbitronic Terahertz Emission in Ferromagnet/Nonmagnet Bilayers
While the initial generation mechanism of picosecond orbital currents remains elusive, we reveal a cascading spin–orbital transport mechanism that induces optically driven terahertz emission in ferromagnet/nonmagnet heterostructures. Using a ferromagnet with strong spin–orbit coupling, we identify a thickness‐driven transition from spin‐dominated to ...
Younghun Kim +7 more
wiley +1 more source
Tailored amine substitution in fluorene and dibenzothiophene derivatives enables systematic control of excited‐state properties and triplet population. Combined photophysical studies, TD‐DFT calculations and time‐resolved EPR reveal how charge‐transfer character, sulfur‐induced spin–orbit coupling and triplet manifold engineering cooperate to promote ...
Francesco Ruighi +10 more
wiley +1 more source

