The fiber optic cable networks linking the world are an essential part of modern life. To keep up with ever-increasing demands for more bandwidth, scientists are working to improve the optical amplifiers that boost fiber optic signals across long distances.
Optical amplifier research is focused on glass fibers doped with rare earth elements. The elements, such as erbium and ytterbium, amplify light signals when excited by a laser. Many different combinations of elements have been tried in pursuit of amplifiers operating in different communication wavebands. However, obtaining effective signal amplifications in those rare earth ions is challenging and requires advanced materials and manufacturing. And to be commercially useful, the glass must be both stable and low-loss, requiring a little energy to boost signals.
An experimental glass developed by a team from Dalian Polytechnic University in China and the City University of Hong Kong solves some of these manufacturing problems. The researchers incorporated heavy metal and alkali/alkaline earth elements such as lead, bismuth, gallium, lithium, potassium, and barium in an oxide glass doped with trivalent samarium rare earth ion. Among oxide glasses, the maximum phonon energy of these materials is nearly the lowest, which may induce multi-channel fluorescence emissions and obvious enhancement of quantum efficiencies of samarium ions.
During laboratory tests, the samarium glass released infrared energy at a wavelength of 1185 nanometers – within the window of fiber optical telecommunications – among other wavelengths. The results, reported in the Journal of Applied Physics, published by the American Institute of Physics (AIP), indicate adding samarium to heavy metal gallate glass is worth exploring for use in both fiber optic networks and lasers.
The article, "Optical evaluation of multi-channel radiative transitions originating from 4G5/2 level of Sm3+ in heavy-metal-gallate glasses" by Hai Lin et al will appear in the Journal of Applied Physics. See: http://jap.aip.org/
ABOUT Journal of Applied Physics
Journal of Applied Physics is the American Institute of Physics' (AIP) archival journal for significant new results in applied physics; content is published online daily, collected into two online and printed issues per month (24 issues per year). The journal publishes articles that emphasize understanding of the physics underlying modern technology, but distinguished from technology on the one side and pure physics on the other. See: http://jap.aip.org/
The American Institute of Physics is a federation of 10 physical science societies representing more than 135,000 scientists, engineers, and educators and is one of the world's largest publishers of scientific information in the physical sciences. Offering partnership solutions for scientific societies and for similar organizations in science and engineering, AIP is a leader in the field of electronic publishing of scholarly journals. AIP publishes 12 journals (some of which are the most highly cited in their respective fields), two magazines, including its flagship publication Physics Today; and the AIP Conference Proceedings series. Its online publishing platform Scitation hosts nearly two million articles from more than 185 scholarly journals and other publications of 28 learned society publishers.