title: Surface-Enhanced Femtosecond Stimulated Raman Spectroscopy at 1 MHz Repetition Rates.
abstract: Surface-enhanced femtosecond stimulated Raman spectroscopy (SE-FSRS) is an ultrafast Raman technique that combines the sensitivity of surface-enhanced Raman scattering with the temporal resolution of femtosecond stimulated Raman spectroscopy (FSRS). Here, we present the first successful implementation of SE-FSRS using a 1 MHz amplified femtosecond laser system. We compare SE-FSRS and FSRS spectra measured at 1 MHz and 100 kHz using both equal pump average powers and equal pump energies to demonstrate that higher repetition rates allow spectra with higher signal-to-noise ratios to be obtained at lower pulse energies, a significant advance in the implementation of SE-FSRS. The ability to use lower pulse energies significantly mitigates sample damage that results from plasmonic enhancement of high-energy ultrafast pulses. As a result of the improvements to SE-FSRS developed in this Letter, we believe that SE-FSRS is now poised to become a powerful tool for studying the dynamics of plasmonic materials and adsorbates thereon.
authors: Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States.
authors: Lauren E
authors: LE
authors: Buchanan
authors: Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States.
authors: Natalie L
authors: NL
authors: Gruenke
authors: Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States.
authors: Michael O
authors: MO
authors: McAnally
authors: Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States.
authors: Bogdan
authors: B
authors: Negru
authors: Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States.
authors: Hannah E
authors: HE
authors: Mayhew
authors: Department of Chemistry, University of California-Irvine , Irvine, California 92697, United States.
authors: Vartkess A
authors: VA
authors: Apkarian
authors: Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States.
authors: George C
authors: GC
authors: Schatz
authors: Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States.
authors: Richard P
authors: RP
authors: Van Duyne