Publications by authors named "Y Messaddeq"
In this Letter, over-correction of spherical aberration is used to counteract nonlinear effects such as Kerr self-focusing and plasma effects, resulting in more spherical and small-sized femtosecond laser-inscribed voxels within nonlinear materials. By strategically redirecting marginal focusing rays toward the beginning of the laser modification zone, the induced plasma prevents any rays from causing a structural modification beyond this zone, irrespective of any focus elongation caused by nonlinear effects. The method has been effectively validated across a range of materials, including ZnS, ZnSe, BIG, GeS, and SiO.
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- The study focuses on accurately characterizing excited-state absorption (ESA) in erbium-doped fibers (EDFs) using a method that combines ON/OFF pumping and a supercontinuum source with a tunable filter.
- By normalizing the ESA profile to its peak value, the researchers facilitate comparisons between samples regardless of their erbium concentration.
- The research also explores how various chemical elements and their concentrations, particularly optimizing aluminum content, can enhance erbium solubility while minimizing negative ESA impacts, aiding in the development of more efficient L-band erbium-doped fiber amplifiers.
Article Synopsis
- - Low back pain (LBP) is a major global disability issue, and effective clinical assessment tools are currently lacking; abnormal muscle control and fatigue are key factors involved.
- - A study evaluated a new flexible surface electromyography (sEMG) system using PEVA electrodes and compared it with a traditional system, measuring muscle activity during two clinical tests for LBP assessment.
- - The new sEMG system demonstrated similar sensitivity and validity to the traditional system in detecting muscle fatigue and activation patterns, suggesting its potential as a reliable tool for LBP assessment.
Bi-doped glasses and optical fibers are extensively studied since they present broadband optical amplification in the near-infrared region (NIR), in which the optical telecommunication industry greatly depends for the transmission of optical signals. There are many scientific challenges about the NIR luminescent emissions from Bi ions, such as understanding its origin and further improving the associated optical amplification capacity. In this work, Bi-doped germanosilicate glass compositions with ultrabroadband NIR luminescence were fabricated, in the range of 925-1630 nm, which covers O, E, S, C, and L-telecommunication bands.
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