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Updated: Aug 15, 2026

Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional π-conjugate Systems
Published on: February 10, 2020
Visible and UV coherent Raman spectroscopy of dipicolinic acid
Dmitry Pestov1, Miaochan Zhi, Zoe-Elizabeth Sariyanni
1Institute for Quantum Studies, Texas A&M University, College Station, TX 77843-4242, USA.
Abstract:
We use time-resolved coherent Raman spectroscopy to obtain molecule-specific signals from dipicolinic acid (DPA), which is a marker molecule for bacterial spores. We use femtosecond laser pulses in both visible and UV spectral regions and compare experimental results with theoretical predictions. By exciting vibrational coherence on more than one mode simultaneously, we observe a quantum beat signal that can be used to extract the parameters of molecular motion in DPA. The signal is enhanced when an UV probe pulse is used, because its frequency is near-resonant to the first excited electronic state of the molecule. The capability for unambiguous identification of DPA molecules will lead to a technique for real-time detection of spores.
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