A three-beam femtosecond stimulated Raman scattering (SRS) scheme is formulated and demonstrated to simultaneously induce two different SRS processes associated with Raman-active modes in the same molecule. Two SR gains involving a common pump pulse are coupled and compete: As one of the Stokes beam intensities increases, the other SRS is selectively suppressed. We provide theoretical description and experimental evidence that the selective suppression behavior is due to the limited number of pump photons used for both of the two SRS processes when an intense depletion beam induces one SRS process. The maximum suppression efficiency was ∼60% with our experimental setup, where the SR gain of the ring breathing mode of benzene is the target SRS signal, which is allowed to compete with another SRS process, induced by an intense depletion beam, of the CH stretching mode. We anticipate a potential of this new switching-off concept in super-resolution label-free microscopy.
Bibliographical noteFunding Information:
This work was supported by Samsung Science and Technology Foundation SSTF-BA1501-08 for S.-H.S and the Institute for Basic Science IBS-R023-D1 for M.C. and PB2017044 for H.R. We thank Yugyeong Kim for help on performing the experiment. All SRS measurements were performed in the femtosecond Multidimensional Laser Spectroscopic System (FMLS) at the Korea Basic Science Institute.
© 2017 American Chemical Society.
ASJC Scopus subject areas
- Materials Science(all)
- Physical and Theoretical Chemistry