We present a terahertz spectroscopic study of polar ferrimagnet FeZnMo_{3}O_{8}. Our main finding is a giant high-temperature optical diode effect, or nonreciprocal directional dichroism, where the transmitted light intensity in one direction is over 100 times lower than intensity transmitted in the opposite direction. The effect takes place in the paramagnetic phase with no long-range magnetic order in the crystal, which contrasts sharply with all existing reports of the terahertz optical diode effect in other magnetoelectric materials, where the long-range magnetic ordering is a necessary prerequisite. In FeZnMo_{3}O_{8}, the effect occurs resonantly with a strong magnetic dipole active transition centered at 1.27 THz and assigned as electron spin resonance between the eigenstates of the single-ion anisotropy Hamiltonian. We propose that the optical diode effect in paramagnetic FeZnMo_{3}O_{8} is driven by single-ion terms in magnetoelectric free energy.
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http://dx.doi.org/10.1103/PhysRevLett.120.037601 | DOI Listing |
RSC Adv
January 2025
Programa de Pós-Graduação em Ciência e Engenharia de Materiais, Universidade Federal Rural do Semi-Árido (UFERSA) CEP 59625-900 Mossoró RN Brazil
Chalcones demonstrate significant absorption in the near ultraviolet-visible spectrum, making them valuable for applications such as solar cells, light-emitting diodes, and nonlinear optics. This study investigates four dibenzalacetone derivatives (DBAd), DBA, DBC, DEP, and DMA, examining the impact of electron-donating and electron-withdrawing groups and conjugation elongation on their electronic structure in solvents of varying polarities. Using the Polarizable Continuum Model (PCM) and time-dependent density functional theory (TD-DFT), we characterized the excited states of these compounds.
View Article and Find Full Text PDFNeurophotonics
January 2025
California Institute of Technology, Department of Electrical Engineering, Pasadena, California, United States.
Significance: Cerebral blood flow (CBF) and cerebral blood volume (CBV) are key metrics for regional cerebrovascular monitoring. Simultaneous, non-invasive measurement of CBF and CBV at different brain locations would advance cerebrovascular monitoring and pave the way for brain injury detection as current brain injury diagnostic methods are often constrained by high costs, limited sensitivity, and reliance on subjective symptom reporting.
Aim: We aim to develop a multi-channel non-invasive optical system for measuring CBF and CBV at different regions of the brain simultaneously with a cost-effective, reliable, and scalable system capable of detecting potential differences in CBF and CBV across different regions of the brain.
Adv Mater
January 2025
Department of Physics, SUNY University at Buffalo, Buffalo, NY, 14220, USA.
Quasi-2D perovskite made with organic spacers co-crystallized with inorganic cesium lead bromide inorganics is demonstrated for near unity photoluminescence quantum yield at room temperature. However, light emitting diodes made with quasi-2D perovskites rapidly degrade which remains a major bottleneck in this field. In this work, It is shown that the bright emission originates from finely tuned multi-component 2D nano-crystalline phases that are thermodynamically unstable.
View Article and Find Full Text PDFSci Bull (Beijing)
January 2025
Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou 215123, China; Macao Institute of Materials Science and Engineering (MIMSE), MUST-SUDA Joint Research Center for Advanced Functional Materials, Zhuhai MUST Science and Technology Research Institute, Macau University of Science and Technology, Macao 999078, China; Institute of Organic Optoelectronics (IOO), Jiangsu Industrial Technology Research Institute (JITRI), Suzhou 215200, China. Electronic address:
High-quality quantum dots (QDs) possess superior electroluminescent efficiencies and ultra-narrow emission linewidths are essential for realizing ultra-high definition QD light-emitting diodes (QLEDs). However, the synthesis of such QDs remains challenging. In this study, we present a facile high-temperature successive ion layer adsorption and reaction (HT-SILAR) strategy for the growth of precisely tailored ZnCdSe/ZnSe shells, and the consequent production of high-quality, large-particle, alloyed red CdZnSe/ZnCdSe/ZnSe/ZnS/CdZnS QDs.
View Article and Find Full Text PDFNutrients
January 2025
Graduate Program of Nutrition Science, School of Life Science, National Taiwan Normal University, Taipei 11677, Taiwan.
The widespread use of light-emitting diodes (LEDs) has increased blue light (BL) exposure, raising concerns about its potential adverse effects on ocular health. Prolonged exposure to BL has been implicated in the pathogenesis of various retinal disorders, including age-related macular degeneration (AMD), primarily through mechanisms involving oxidative stress and inflammation mediated by the overproduction of reactive oxygen species (ROS). This review synthesizes current evidence on the photoprotective properties of dietary bioactive compounds, (e.
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