Operational Regimes in Picosecond and Femtosecond Pulse-Excited Ultrahigh Vacuum SERS

Eric A. Pozzi, Natalie L. Gruenke, Naihao Chiang, Dmitry V. Zhdanov, Nan Jiang, Tamar Seideman, George C Schatz, Mark C Hersam, Richard P. Van Duyne

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

We report a systematic study performed in ultrahigh vacuum designed to identify the laser excitation regimes in which plasmonically enhanced ultrashort pulses may be used to nondestructively probe surface-bound molecules. A nondestructive, continuous-wave spectroscopic probe is used to monitor the effects of four different femtosecond- and picosecond-pulsed beams on the SER signals emanating from molecular analytes residing within plasmonically enhanced fields. We identify the roles of plasmonic amplification and alignment with a molecular electronic transition on the observed changes in the SER signals. Our results indicate that overlap of the laser wavelength with the plasmon resonance is the dominant contributor to signal degradation. In addition, signal loss for a given irradiation condition is observed only for molecules residing in hot spots above a threshold enhancement. Identification of suitable laser energy density ranges demonstrates the importance of considering these parameters when implementing SERS in the presence of pulsed irradiation.

Original languageEnglish
Pages (from-to)2971-2976
Number of pages6
JournalJournal of Physical Chemistry Letters
Volume7
Issue number15
DOIs
Publication statusPublished - Aug 4 2016

    Fingerprint

ASJC Scopus subject areas

  • Materials Science(all)

Cite this

Pozzi, E. A., Gruenke, N. L., Chiang, N., Zhdanov, D. V., Jiang, N., Seideman, T., Schatz, G. C., Hersam, M. C., & Van Duyne, R. P. (2016). Operational Regimes in Picosecond and Femtosecond Pulse-Excited Ultrahigh Vacuum SERS. Journal of Physical Chemistry Letters, 7(15), 2971-2976. https://doi.org/10.1021/acs.jpclett.6b01151