We experimentally demonstrate the generation of microwave signals with linewidths below 3 Hz and a tuning range over 35 GHz from a semiconductor laser subject to optical injection and opto-electronic feedback. The feedback loop uses neither a microwave spectral filter nor an amplifier to achieve a reduction in the microwave linewidth of six orders of magnitude. Two microwave frequencies, 25.4 and 45.9 GHz, are chosen to highlight single-sideband phase measurements of -105 and -95 dBc/Hz at a 10-kHz offset, respectively. Finally, we demonstrate that longer-term stability can be further improved via asymmetric mutual injection.
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http://dx.doi.org/10.1364/OL.42.003181 | DOI Listing |
Sci Rep
January 2025
THz-Photonics Group, Institut für Hochfrequenztechnik, Technische Universität Braunschweig, 38106, Braunschweig, Germany.
Space division multiplexing (SDM) with Hermite Gaussian (HG) modes, for instance, can significantly boost the transmission link capacity. However, SDM is not suitable in existing single mode fiber networks, and in long-distance wireless, microwave, THz or optical links, the far-field beam distribution may present a problem. Recently it has been demonstrated, that time domain HG modes can be employed to enhance the link capacity.
View Article and Find Full Text PDFNat Commun
January 2025
State Key Laboratory for Extreme Photonics and Instrumentation, Center for Optical & Electromagnetic Research, College of Optical Science and Engineering, International Research Center for Advanced Photonics (Haining), Zhejiang University, Hangzhou, China.
Silicon photonic signal processors promise a new generation of signal processing hardware with significant advancements in processing bandwidth, low power consumption, and minimal latency. Programmable silicon photonic signal processors, facilitated by tuning elements, can reduce hardware development cycles and costs. However, traditional programmable photonic signal processors based on optical switches face scalability and performance challenges due to control complexity and transmission losses.
View Article and Find Full Text PDFInt J Nanomedicine
January 2025
Key Laboratory of Medical Cell Biology, Affiliated Hospital of Inner Mongolia Medical University, Hohhot, Inner Mongolia, People's Republic of China.
Introduction: The anti-cancer properties of zinc oxide-doped carbon dots (CDs/ZnO) in inhibiting triple-negative breast cancer (TNBC) progression merit more investigation.
Methods: With citric acid as the carbon source, urea applied as the nitrogen source, and zinc oxide (ZnO) used as a reactive dopant, CDs/ZnO were synthesized by microwave heating in the current study, followed by the characterization and biocompatibility assessments. Subsequently, the anti-cancer capabilities of CDs/ZnO against TNBC progression were evaluated by various biochemical and molecular techniques, including viability, proliferation, migration, invasion, adhesion, clonogenicity, cell cycle distribution, apoptosis, redox homeostasis, metabolome, and transcriptome assays of MDA-MB-231 cells.
Phytomedicine
December 2024
College of Food Science and Technology, Zhejiang University of Technology, Hangzhou, 310014, China. Electronic address:
Background: Gut dysbiosis, chronic diseases, and microbial recurrent infections concerns have driven the researchers to explore phytochemicals from medicinal and food homologous plants to modulate gut microbiota, mitigate diseases, and inhibit pathogens. Gingerols have attracted attention as therapeutic agents due to their diverse biological activities like gut microbiome regulation, gastro-protective, anti-inflammatory, anti-microbial, and anti-oxidative effects.
Purpose: This review aimed to summarize the gingerols health-promoting potential, specifically focusing on the regulation of gut microbiome, attenuation of disease symptoms, mechanisms of action, and signaling pathways involved.
3D Print Addit Manuf
December 2024
Escuela de Ingeniería Eléctrica, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile.
This article presents a high-frequency characterization from 1 up to 10 GHz of electroplated conductive filaments in 3D printed microwave topologies. This study implements different microstrip lines and antennas to compare their performance as-is and with the electroplating process. The results for the microstrip lines show a significant decrease in losses for the electroplated devices, even reaching loss levels of pure copper devices.
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