Development of a broadband picosecond infrared spectrometer and its incorporation into an existing ultrafast time-resolved resonance Raman, UV/visible, and fluorescence spectroscopic apparatus

Michael Towrie, David C. Grills, Joanne Dyer, Julia A. Weinstein, Pavel Matousek, Robin Barton, Philip D. Bailey, Naresh Subramaniam, Wai Ming Kwok, Chensheng Ma, David Phillips, Anthony W. Parker, Michael W. George

Research output: Journal article publicationJournal articleAcademic researchpeer-review

139 Citations (Scopus)


We have constructed a broadband ultrafast time-resolved infrared (TRIR) spectrometer and incorporated it into our existing time-resolved spectroscopy apparatus, thus creating a single instrument capable of performing the complementary techniques of femto-/picosecond time-resolved resonance Raman (TR3), fluorescence, and UV/visible/infrared transient absorption spectroscopy. The TRIR spectrometer employs broadband (150 fs, ∼150 cm-1FWHM) mid-infrared probe and reference pulses (generated by difference frequency mixing of near-infrared pulses in type I AgGaS2), which are dispersed over two 64-element linear infrared array detectors (HgCdTe). These are coupled via custom-built data acquisition electronics to a personal computer for data processing. This data acquisition system performs signal handling on a shot-by-shot basis at the 1 kHz repetition rate of the pulsed laser system. The combination of real-time signal processing and the ability to normalize each probe and reference pulse has enabled us to achieve a high sensitivity on the order of ΔOD ∼ 10-4-10-5with 1 min of acquisition time. We present preliminary picosecond TRIR studies using this spectrometer and also demonstrate how a combination of TRIR and TR3spectroscopy can provide key information for the full elucidation of a photochemical process.
Original languageEnglish
Pages (from-to)367-380
Number of pages14
JournalApplied Spectroscopy
Issue number4
Publication statusPublished - 1 Apr 2003
Externally publishedYes


  • Array detector
  • Broadband
  • Charge-transfer excited states
  • DNA probes
  • Fluorescence
  • Infrared
  • Kerr gate
  • Photopolymerization initiators
  • Resonance Raman
  • Ultrafast time-resolved spectroscopy

ASJC Scopus subject areas

  • Instrumentation
  • Spectroscopy

Cite this