Ultrafast Coherent Raman Scattering at Plasmonic Nanojunctions
Autor: | V. Ara Apkarian, Kevin T. Crampton, Alexander Fast, Steven Yampolsky, Alba Alfonso-Garcia, Mayukh Banik, Dmitry A. Fishman, Eric O. Potma, Aram Zeytunyan, Faezeh Tork Ladani |
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Rok vydání: | 2016 |
Předmět: |
Materials science
business.industry 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Molecular physics 0104 chemical sciences Surfaces Coatings and Films Electronic Optical and Magnetic Materials symbols.namesake General Energy Optics X-ray Raman scattering Femtosecond symbols Spontaneous emission Coherent anti-Stokes Raman spectroscopy Physical and Theoretical Chemistry 0210 nano-technology business Raman spectroscopy Ultrashort pulse Plasmon Raman scattering |
Zdroj: | The Journal of Physical Chemistry C. 120:20943-20953 |
ISSN: | 1932-7455 1932-7447 |
Popis: | Surface-enhanced coherent anti-Stokes Raman scattering (SECARS) measurements carried out on individual nanosphere dimer nantennas are presented. The ν-domain and t-domain CARS measurements in the few-molecule limit are contrasted as vibrational autocorrelation and cross-correlation, respectively. We show that in coherent Raman spectroscopies carried out with ultrashort pulses, the effect of surface enhancement is to saturate stimulated steps at very low incident intensities (100 fJ in 100 fs pulses), and the principal consideration in sensitivity is the effective quadratic enhancement of spontaneous emission cross sections, σ* = (EL/Eo)2σ. Through multicolor femtosecond SECARS measurements we show that beside enhancement factors, an effective plasmon mode matching consideration controls the interplay between coherent electronic Raman scattering on the nantenna and vibrational Raman scattering on its molecular load. Through extensive measurements on individual nantennas, we establish the tolerable average ... |
Databáze: | OpenAIRE |
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