A single-mode polarization-maintaining fiber doped to increase the Raman gain while suppressing stimulated Brillouin scattering (SBS) was utilized in a single-stage counter-pumped Raman fiber amplifier. The SBS suppression was achieved through the acoustic tailoring of the core. A pump probe experiment was conducted to characterize the Brillouin gain and indicated the existence of multiple Brillouin peaks. When the amplifier was seeded with approximately 15 mW of 1178 nm light, 11.5 W of cw output power was obtained with a linewidth ≤2 MHz. The application of a thermal gradient to further mitigate the SBS process increased the output power to 18 W, thus providing a net amplifier gain >30 dB.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1364/OL.37.001766 | DOI Listing |
J Biophotonics
January 2025
Laser Biomedical Applications Division, Raja Ramanna Centre for Advanced Technology, Indore, India.
Availability of a suitable tool for carrying out non-invasive measurement of Raman signatures in situ, from biological tissues having low Raman cross section is a clinically unmet need faced with manifold challenges. A Raman probe can prove to be an invaluable component of clinical Raman diagnostic systems. We present development of a Raman probe capable of measuring artefact free Raman spectra of biological tissues in situ.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
Department of Mechanical, Robotics and Energy Engineering, Dongguk University, Seoul 04620, Republic of Korea. Electronic address:
This paper introduces a highly absorbent and sensitive cellulose nanofiber (CNF)/gold nanorod (GNR)@Ag surface-enhanced Raman scattering (SERS) sensor, fabricated using the vacuum filtration method. By optimizing the Ag thickness in the GNR@Ag core-shell structures and integrating them with CNFs, optimal SERS hotspots were identified using the Raman probe molecule 4-aminothiophenol (4-ATP). To concentrate pesticides extracted from fruit and vegetable surfaces, we utilized the evaporation enrichment effect using hydrophilic CNF and hole-punched hydrophobic polydimethylsiloxane (PDMS).
View Article and Find Full Text PDFACS EST Air
January 2025
Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States.
Due to the increased prevalence of plastic pollution globally, atmospheric deposition of microplastics (MPs) is a significant issue that needs to be better understood to identify potential consequences for human health. This study is the first to quantify and characterize atmospheric MP deposition in the Eastern United States. Passive sampling was conducted at two locations within the Eastern United States, specifically in remote South Central Appalachia, from March to September 2023.
View Article and Find Full Text PDFIn this Letter, we report an ultraflat high-power supercontinuum (SC) based on a low-loss short-length fluorotellurite fiber. A novel high-peak power dual-Raman soliton femtosecond laser is used as a pump source, which effectively extends the mid-infrared SC spectral range and enhances the flatness of the SC. Finally, we obtained a 10.
View Article and Find Full Text PDFThis study reports the observation of complete orthogonally polarized Raman scattering (OPRS) in a 1.0-km high-birefringence fiber (HBF). An incident pump pulse at 1560 nm with an energy of 2.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!