Results 111 to 120 of about 59,947 (271)

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

Advanced 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, Víctor Anthony García Rivera, Stéphan Cagnon, Souleymane Toubou Bah, Younès Messaddeq, Euclydes Marega Junior   +5 more
wiley   +1 more source

Reconfigurable Millimeter-Wave Generation via Mutually Injected Spin-VCSELs

Photonics
We propose a novel scheme for generating high-frequency millimeter-wave signals by exploiting period-one (P1) dynamics in a mutual injection configuration of two spin-polarized vertical-cavity surface-emitting lasers (spin-VCSELs).
Yichuan Xiong, Yu Huang, Pei Zhou, Kuenyao Lau, Nianqiang Li   +4 more
doaj   +1 more source

Broadband Directional Thermal Radiation with Asymmetric Femtosecond Laser‐Processed Surfaces

Advanced Optical Materials, EarlyView.
Femtosecond laser processing is used to scalably create self‐organized angled microstructures which exhibit highly directional emissivity that occurs for all polarizations. Laser parameters are tuned to alter the surface features, control the direction of emission, and enhance the directional emissivity. Electromagnetic modeling is performed to analyze
Andrew Butler, Andrew Reicks, Jack Schulz, Patrick Hayden, Alireza Kalantari Dehaghi, Kira Marr, Linxiao Zhu, Christos Argyropoulos, Craig Zuhlke   +8 more
wiley   +1 more source

A shared aperture multiport antenna for rural wireless communication and safety monitoring using TVWS, ISM, and 5G mmWave bands

Scientific Reports
To accommodate the antenna demand for rural communication and safety monitoring a shared aperture muti-port antenna sensor is presented for three different operating frequencies covering both Sub- 6 GHz and 5G millimeter-wave bands. The antenna sensor is
Md Abu Sufian, Sang-Min Lee, Domin Choi, Jaemin Lee, Dongkyu Sim, Minyoung Song, Nam Kim   +6 more
doaj   +1 more source

Multi‐Dielectric Metasurfaces for Ultrabright, Tunable Structural Color and Reconfigurable Optical Filtering with Extraordinarily Large Color Span

Advanced Optical Materials, EarlyView.
Structural color generation is an emerging field for digital display and printing applications. This report presents a novel truncated‐cone design and the first use of GaP sandwiched between two layers of TiO2, demonstrating ultra‐bright, tunable colors with a record color gamut.
Md Rumon Miah, Yavuz Selim Aydın, Hilmi Volkan Demir   +2 more
wiley   +1 more source

Selective Reflection of Chiral Ferroelectric Nematic Liquid Crystals Tuned by Electric Field Along the Helix Axis

Advanced Optical Materials, EarlyView.
It is demonstrated that in chiral ferroelectric nematic liquid crystals sandwiched between electrically conducting transparent plates, the reflection color can be reversibly tuned by electric fields applied along the helix axis. The proposed theoretical model, assuming field‐induced coiling of the helix axis, accounts for all observations.
Md Sakhawat Hossain Himel, Rohan Dharmarathna, James T. Gleeson, Robert J. Twieg, Samuel Sprunt, Antal Jákli   +5 more
wiley   +1 more source

V-Band Multiport Heterodyne Receiver for High-Speed Communication Systems

EURASIP Journal on Wireless Communications and Networking, 2007
A V-band receiver using a MHMIC multiport circuit is presented in this paper. The millimeterwave frequency conversion is performed using a passive circuit, the multiport, and related power detectors, avoiding the conventional millimeter-wave active ...
Tatu Serioja O, Moldovan Emilia
doaj  

Probing Near‐Field EM Fluctuations in Superparamagnetic CoFeB With NV Quantum Dephasometry

Advanced Optical Materials, EarlyView.
We non‐invasively investigate the superparamagnetic spin dynamics of a 1.1 nm CoFeB layer by probing its near‐field EM fluctuations using NV centers‐based quantum dephasometry. Our findings are further supported by theoretical modeling and SQUID‐based magnetization characterization. These results provide critical insight into the magnetization dynamics
Shoaib Mahmud, Wei Zhang, Pronoy Das, Angshuman Deka, Wenbo Sun, Zubin Jacob   +5 more
wiley   +1 more source

Vanadium dioxide thin films integrated with printed circuit board enables low-cost, reconfigurable millimeter-wave devices

Communications Engineering
Millimeter-wave switches are essential for reconfigurable and adaptive communication systems, yet current solutions often face trade-offs between performance, scalability, and cost. Here we present a scalable, high performance and cost-effective approach
Amir Afshani, Wenqiang Xiang, Tarek Djerafi, Mohamed Chaker   +3 more
doaj   +1 more source

Analysis and Optimization for Robust Millimeter-Wave Communications.

, 2021
Spectrum scarcity is a longstanding problem in mobile telecommunications networks. Specifically, accommodating the ever-growing data rate and communications demand in the extensively used spectrum between 800 MHz and 6 GHz is becoming more challenging.
openaire   +2 more sources