Femtosecond Stimulated Raman Spectroscopy

Femtosecond stimulated Raman spectroscopy (FSRS) is a relatively recent yet moderately widespread time-resolved spectroscopy technique for observing changes in the vibrational structure of optically excited molecular systems.

At its core, FSRS is a multi-pulse technique that can be summarized as follows. First, an ultrashort actinic pump pulse acts on a molecular system in its ground state and initiates the photoreaction. Then, a pair of temporally delayed pulses probes the successive photoevolution. Here, a picosecond Raman pump and broadband femtosecond Raman probe pulse are used. The temporal overlap of these two pulses brings coherence in the excited state, resulting in the amplification of the Stokes and anti-Stokes frequencies within the probe field, i.e., stimulated Raman emission. Since a high degree of coherence is achieved only during the short temporal overlap of the Raman pump and probe pulses, FSRS spectroscopy offers a high resolution in both spectral and temporal domains.

FSRS is readily available in the HARPIA spectroscopy system, providing vibrational structural information with < 200 fs temporal and < 10 cm-1 spectral resolution. Raman pump can be generated using SHBC, if a fixed-wavelength output at 515 nm is sufficient, or SHBC together with ORPHEUS-PS, if a wide tuning range is desired. The system is pumped by a PHAROS femtosecond laser.

  • Market-leading sensitivity
  • 330 nm – 24 μm spectral range
  • Probe delay ranges from 2 to 8 ns
  • Pump pulse energies down to nJ
  • Cryostat and peristaltic pump support
  • Delivery of an additional femtosecond or picosecond beam
  • Polarization, intensity, and delay control
  • Femtosecond stimulated Raman scattering (FSRS) support
  • Z-scan support
  • 515 nm output
  • < 10 cm-1 spectral bandwidth
  • 2 – 4 ps pulse duration
  • > 30% conversion efficiency
  • Compact footprint
  • 210 – 4800 nm tuning range
  • 800 fs – 3 ps pulse duration
  • < 20 cm-1 spectral bandwidth
  • Nearly bandwidth-limited output
  • Up to 100 kHz repetition rate
  • High output stability
  • 190 – 16000 nm tuning range
  • Single-shot – 2 MHz repetition rate
  • Up to 80 W pump power
  • Up to 2 mJ pump pulse energy
  • Completely automated
  • 100 fs – 20 ps tunable pulse duration
  • 4 mJ maximum pulse energy
  • 20 W maximum output power
  • Single-shot – 1 MHz repetition rate
  • BiBurst
  • Automated harmonic generators (up to 5th harmonic)

Spontaneous versus Stimulated Surface-Enhanced Raman Scattering of Liquid Water

P. Filipczak, M. Pastorczak, T. Kardaś, M. Nejbauer, C. Radzewicz, and M. Kozanecki, The Journal of Physical Chemistry C 3 (125), 1999-2004 (2020).

Incoherent phonon population and exciton-exciton annihilation dynamics in monolayer WS2 revealed by time-resolved Resonance Raman scattering

S. Han, C. Boguschewski, Y. Gao, L. Xiao, J. Zhu, and P. H. M. van Loosdrecht, Optics Express 21 (27), 29949 (2019).

A tunable time-resolved spontaneous Raman spectroscopy setup for probing ultrafast collective excitation and quasiparticle dynamics in quantum materials

R. B. Versteeg, J. Zhu, P. Padmanabhan, C. Boguschewski, R. German, M. Goedecke, P. Becker, and P. H. M. van Loosdrecht, Structural Dynamics 4 (5), 044301 (2018).

Exciton and phonon dynamics in highly aligned 7-atom wide armchair graphene nanoribbons as seen by time-resolved spontaneous Raman scattering

J. Zhu, R. German, B. V. Senkovskiy, D. Haberer, F. R. Fischer, A. Grüneis, and P. H. M. van Loosdrecht, Nanoscale 37 (10), 17975-17982 (2018).

Selective suppression of CARS signal with three-beam competing stimulated Raman scattering processes

D. S. Choi, B. J. Rao, D. Kim, S. Shim, H. Rhee, and M. Cho, Physical Chemistry Chemical Physics 25 (20), 17156-17170 (2018).

Selective Suppression of Stimulated Raman Scattering with Another Competing Stimulated Raman Scattering

D. Kim, D. S. Choi, J. Kwon, S. Shim, H. Rhee, and M. Cho, The Journal of Physical Chemistry Letters 24 (8), 6118-6123 (2017).

Structural Heterogeneity in the Localized Excited States of Poly(3-hexylthiophene)

W. Yu, T. J. Magnanelli, J. Zhou, and A. E. Bragg, The Journal of Physical Chemistry B 22 (120), 5093-5102 (2016).