By a News Reporter-Staff News Editor at Science Letter -- Researchers detail new data in Science. According to news reporting originating in Urbana, Illinois, by NewsRx journalists, research stated, "Plasmonic nanostructures are of great current interest as chemical sensors, in vivo imaging agents, and for photothermal therapeutics. We study continuous-wave (cw) and pulsed-laser excitation of aqueous suspensions of Au nanorods as a model system for secondary light emission from plasmonic nanostructures."
The news reporters obtained a quote from the research from the University of Illinois, "Resonant secondary emission contributes significantly to the background commonly observed in surface-enhanced Raman scattering and to the light emission generated by pulsed-laser excitation of metallic nanostructures that is often attributed to two-photon luminescence. Spectra collected using cw laser excitation at 488 nm show an enhancement of the broad spectrum of emission at the electromagnetic plasmon resonance of the nanorods. The intensity of anti-Stokes emission collected using cw laser excitation at 785 nm is described by a 300 K thermal distribution of excitations. Excitation by subpicosecond laser pulses at 785 nm broadens and increases the intensity of the anti-Stokes emission in a manner that is consistent with electronic Raman scattering by a high-temperature distribution of electronic excitations predicted by a two-temperature model. Broadening of the pulse duration using an etalon reduces the intensity of anti-Stokes emission in quantitative agreement with the model."
According to the news reporters, the research concluded: "Experiments using a pair of subpicosecond optical pulses separated by a variable delay show that the timescale of resonant secondary emission is comparable to the timescale for equilibration of electrons and phonons."
For more information on this research see: Resonant secondary light emission from plasmonic Au nanostructures at high electron temperatures created by pulsed-laser excitation. Proceedings of the National Academy of Sciences of the United States of America, 2014;111(3):906-911. Proceedings of the National Academy of Sciences of the United States of America can be contacted at: Natl Acad Sciences, 2101 Constitution Ave NW, Washington, DC 20418, USA. (National Academy of Sciences - www.nasonline.org/; Proceedings of the National Academy of Sciences of the United States of America - www.nasonline.org/publications/pnas/)
Our news correspondents report that additional information may be obtained by contacting J.Y. Huang, University of Illinois, Mat Res Lab, Urbana, IL 61801, United States. Additional authors for this research include W. Wang, C.J. Murphy and D.G. Cahill (see also Science).
Keywords for this news article include: Urbana, Science, Illinois, United States, North and Central America
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