Results 71 to 80 of about 20,118 (299)

Tuning Excitonic Properties and Charge Carrier Dynamics by Halide Alloying in Cs3Bi2(Br1−xIx)9 Semiconductors

Advanced Optical Materials, EarlyView.
This work studies the effect of halide alloying in Cs3Bi2(Br1−xIx)9 (0 ≤ x ≤ 1) semiconductors. The x = 0.6 shows the smallest bandgap, lowest exciton binding energy, and longest charge carrier lifetimes, showing promising properties for optoelectronic and photocatalytic applications.
He Zhao, Eline M. Hutter
wiley   +1 more source

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

Advanced 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, Kazuho Harada, Qian Liu, Isao Morohashi, Xu Fang, Kazuhiko Hirakawa, Ya Zhang   +6 more
wiley   +1 more source

Free Space Optical Communication Systems [PDF]

, 2009
The main advantage of using optical frequencies in free-space communication systems is the high directivity of the propagating optical beam. (In the context of this chapter, the term “free space” refers to unguided optical communications; exoatmospheric environments are referred to as “space.”) When transmitted from an antenna, electromagnetic waves ...
  +4 more sources

Physical-Layer Security in Orbital Angular Momentum Multiplexing Free-Space Optical Communications

IEEE Photonics Journal, 2016
The physical-layer security of a line-of-sight (LOS) free-space optical (FSO) link using orbital angular momentum (OAM) multiplexing is studied. We discuss the effect of atmospheric turbulence to OAM-multiplexed FSO channels.
Xiaole Sun, Ivan B. Djordjevic
doaj   +1 more source

Thermo‐Derived Cholesteric Liquid Crystal Elastomer Pattern with Composite Structural Colors

Advanced Optical Materials, EarlyView.
A thermochromic cholesteric liquid crystal (CLC) oligomer was synthesized for the preparation of CLC elastomer (CLCE) films with dual reflection bands. Subsequently, a CLCE pattern with composite structural colors was prepared, which was suitably applied for decoration and anti‐counterfeiting.
Li Zhong, Yi Li, Wei Liu, Yonggang Yang
wiley   +1 more source

Aerosol Jet Printed Polymer‐Free High Aspect Ratio Quantum Dot Films for Enhanced Color Conversion

Advanced Optical Materials, EarlyView.
Polymer‐free quantum dot color conversion layers are aerosol jet printed at high aspect ratio by tuning the aerosol focus ratio to induce in‐flight droplet drying. Contact‐line pinning suppresses lateral spreading, enabling ∼10 µm‐thick films at ∼50 µm widths with blue light leakage below 0.25% and conversion efficiency approaching 18%, demonstrated ...
Sukyung Choi, Anna Meredith, Hyunsu Cho, Zahra Bahrami, Kevin Schnittker, Joseph Andrews   +5 more
wiley   +1 more source

Controlling the Spatial Coherence of an Optical Source Using a Spatial Filter

Applied Sciences, 2018
This paper presents the theory for controlling the spectral degree of coherence via spatial filtering. Starting with a quasi-homogeneous partially coherent source, the cross-spectral density function of the field at the output of the spatial filter is ...
Milo W. Hyde
doaj   +1 more source

Frontier Progress of Unmanned Aerial Vehicles Optical Wireless Technologies

Sensors, 2020
With the continuous maturity of unmanned aerial vehicles (UAV) in materials, communications, and other related technologies, the UAV industry has developed rapidly in recent years.
Jupeng Ding, Hongye Mei, Chih-Lin I, Hui Zhang, Wenwen Liu   +4 more
doaj   +1 more source

Direct Measurement of the Singlet Lifetime and Photoexcitation Behavior of the Boron Vacancy Center in Hexagonal Boron Nitride

Advanced Optical Materials, EarlyView.
Negatively charged boron vacancy defects in hexagonal boron nitride promise near‐surface quantum sensing, but their internal spin transition rates are only partly understood. This work directly measures the defect's singlet‐state lifetime, 15(3) ns, using a nanosecond rise‐time dual‐pulse photoluminescence‐recovery method, and shows that high laser ...
Richard A. Escalante, Andrew J. Beling, Daniel G. Ang, Niko R. Reed, Justin J. Welter, John W. Blanchard, Cecilia Campos, Edwin Coronel, Klaus Krambrock, Alexandre S. Leal, Paras N. Prasad, Ronald L. Walsworth   +11 more
wiley   +1 more source

Channel Correlation-Based Adaptive Power Transmission for Free-Space Optical Communications

Photonics
Free-space optical (FSO) communication has received widespread attention as a high-bandwidth, low-latency communication technique. However, the scintillation effect caused by atmospheric turbulence leads to intensity fluctuations of the transmission ...
Bai-Shan Zhao, Peng-Fei Lv, Yan-Qing Hong   +2 more
doaj   +1 more source