We demonstrate the generation of wideband frequency sweeps using a semiconductor laser in an optoelectronic feedback loop. The rate and shape of the optical frequency sweep is locked to and determined by the frequency of a reference electronic signal, leading to an agile, high coherence swept-frequency source for laser ranging and 3-D imaging applications. Using a reference signal of constant frequency, a transform-limited linear sweep of 100 GHz in 1 ms is achieved, and real-time ranging with a spatial resolution of 1.5 mm is demonstrated. Further, arbitrary frequency sweeps can be achieved by tuning the frequency of the input electronic signal. Broadband quadratic and exponential optical frequency sweeps are demonstrated using this technique.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1364/OE.17.015991 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Genomic analysis of global Plasmodium vivax populations reveals insights into the evolution of drug resistance.
Nat Commun
December 2024
Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
Increasing reports of chloroquine resistance (CQR) in Plasmodium vivax endemic regions have led to several countries, including Indonesia, to adopt dihydroarteminsin-piperaquine instead. However, the molecular drivers of CQR remain unclear. Using a genome-wide approach, we perform a genomic analysis of 1534 P.
View Article and Find Full Text PDFSystematic surveillance of SARS-CoV-2 reveals dynamics of variant mutagenesis and transmission in a large urban population.
Nat Commun
December 2024
Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, M5G 1X5, Canada.
Highly mutable pathogens generate viral diversity that impacts virulence, transmissibility, treatment, and thwarts acquired immunity. We previously described C19-SPAR-Seq, a high-throughput, next-generation sequencing platform to detect SARS-CoV-2 that we here deployed to systematically profile variant dynamics of SARS-CoV-2 for over 3 years in a large, North American urban environment (Toronto, Canada). Sequencing of the ACE2 receptor binding motif and polybasic furin cleavage site of the Spike gene in over 70,000 patients revealed that population sweeps of canonical variants of concern (VOCs) occurred in repeating wavelets.
View Article and Find Full Text PDFDeep-learning enabled generalized inverse design of multi-port radio-frequency and sub-terahertz passives and integrated circuits.
Nat Commun
December 2024
Department of Electrical and Computer Engineering, Princeton University, Princeton, NJ, USA.
Millimeter-wave and terahertz integrated circuits and chips are expected to serve as the backbone for future wireless networks and high resolution sensing. However, design of these integrated circuits and chips can be quite complex, requiring years of human expertise, careful tailoring of hand crafted circuit topologies and co-design with parameterized and pre-selected templates of electromagnetic structures. These structures (radiative and non-radiative, single-port and multi-ports) are subsequently optimized through ad-hoc methods and parameter sweeps.
View Article and Find Full Text PDFHemodynamic cortical ripples through cyclicity analysis.
Netw Neurosci
December 2024
Coordinated Science Laboratory, University of Illinois, Urbana-Champaign, Urbana, USA.
A fine-grained understanding of dynamics in cortical networks is crucial to unpacking brain function. Resting-state functional magnetic resonance imaging (fMRI) gives rise to time series recordings of the activity of different brain regions, which are aperiodic and lack a base frequency. Cyclicity analysis, a novel technique robust under time reparametrizations, is effective in recovering the temporal ordering of such time series, collectively considered components of a multidimensional trajectory.
View Article and Find Full Text PDFEnhanced physicochemical and antifungal properties of starch bionanocomposites reinforced with nanocellulose and functionalized with AgNPs derived from cocoa bean shell.
Int J Biol Macromol
December 2024
Biotransformation and Organic Biocatalysis Research Group, Department of Exact Sciences, Santa Cruz State University, 45654-370 Ilhéus, Brazil. Electronic address:
This study explored the synergistic combination of silver nanoparticles (AgNPs), eucalyptus-derived nanofibrillated cellulose (NFC) and cassava starch to develop bionanocomposites with advanced properties suitable for sustainable and antifungal packaging applications. The influence of AgNPs synthesized through a green method using cocoa bean shell combined with varying concentrations of NFC were investigated. Morphological (scanning electron microscopy and atomic force microscopy), optical (L*, C*, °hue, and opacity), chemical (Fourier transform infrared spectroscopy), mechanical (puncture force, tensile strength, and Young's modulus), rheological (flow curve and frequency sweeps, strain, and stress), barrier, and hydrophilicity properties (water vapor permeability, solubility, wettability, and contact angle), as well as the antifungal effect against pathogens (Botrytis cinerea, Penicillium expansum, Colletotrichum musae, and Fusarium semitectum), were analyzed.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!