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We present a bias-free photoconductive emitter that uses an array of nanoantennas on an InGaAs layer with a linearly graded Indium composition. The graded InGaAs structure creates a built-in electric field that extends through the entire photoconductive active region, enabling the efficient drift of the photo-generated electrons to the nanoantennas. The nanoantenna geometry is chosen so that surface plasmon waves are excited in response to a 1550 nm optical pump to maximize photo-generated carrier concentration near the nanoantennas, where the built-in electric field strength is maximized. With the combination of the plasmonic enhancement and built-in electric field, high-power terahertz pulses are generated without using any external bias voltage. We demonstrate the generation of terahertz pulses with 860 µW average power at an average optical pump power of 900 mW, exhibiting the highest radiation power compared to previously demonstrated telecommunication-compatible terahertz pulse emitters.
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http://dx.doi.org/10.1364/OE.447733 | DOI Listing |
J Colloid Interface Sci
September 2025
State Key Laboratory of Heavy Oil Processing, College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao 266580, China.
Reaction intermediates (RI) are key factors that directly determine the efficiency of the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). In this study, a local electric field microenvironment was built in a FeNi and MoNi heterostructure (H-FeNiMo/NMF) to induce the redistribution of hydroxyls and protons on the metal sites during the OER and HER. H-FeNiMo/NMF requires only 270 and 155 mV to reach 100 mA cm in alkaline media for OER and HER, respectively.
View Article and Find Full Text PDFNanoscale
September 2025
School of Materials Science and Engineering, Beihang University, Beijing 100191, China.
The challenge of photocatalytic hydrogen production has motivated a targeted search for MXenes as a promising class of materials for this transformation because of their high mobility and high light absorption. High-throughput screening has been widely used to discover new materials, but the relatively high cost limits the chemical space for searching MXenes. We developed a deep-learning-enabled high-throughput screening approach that identified 14 stable candidates with suitable band alignment for water splitting from 23 857 MXenes.
View Article and Find Full Text PDFPhys Chem Chem Phys
September 2025
Jiangxi Provincial Key Laboratory of Multidimensional Intelligent Perception and Control, School of Energy and Mechanical Engineering, Jiangxi University of Science and Technology, Nanchang, 330013, Jiangxi Province, China.
The quest for sustainable and clean energy sources has led to significant research into photocatalytic water splitting, a process that converts solar energy into hydrogen fuel. This study demonstrates constructing a high-performance CdTe/CN van der Waals heterojunction for solar-driven water splitting hydrogen evolution. The proposed CdTe/CN heterojunction, investigated using first-principles calculations, integrates favorable structural stability and features a direct bandgap of 1.
View Article and Find Full Text PDFInt J Cardiol
September 2025
Department of Cardiology, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China. Electronic address:
Background And Aims: Previous cardiac implantable electronic devices (CIEDs) automatically monitored, diagnosed, and stored atrial or ventricular tachyarrhythmias as intracardiac electrograms (EGMs). Abbott's new-generation CIEDs offer pre-event EGM storage (Pre-EGM), recording cardiac electrical activity before arrhythmic events. This study determines whether Pre-EGM provides additional diagnostic information for arrhythmic events.
View Article and Find Full Text PDFAdv Mater
September 2025
KU-KIST Graduate School of Converging Science and Technology, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea.
Metal-nitrogen-carbon (M-N-C) catalysts display considerable potential as cost-effective alternatives to noble metals in oxygen electrocatalysis. However, uncontrolled atomic migration and random structural rearrangement during pyrolysis often lead to disordered coordination environments and sparse active sites, fundamentally limiting their intrinsic catalytic activities and long-term durability. Herein, a novel strategy is reported for use in directionally regulating atomic migration pathways via the incorporation of a foreign metal (La).
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