Femtosecond Raman‐induced Kerr effect spectroscopy

We report the development of a new vibrational technique called Femtosecond Raman‐Induced Kerr Effect Spectroscopy (FRIKES). This technique combines a narrow‐bandwidth picosecond Raman pump pulse with a broadband femtosecond probe pulse to produce high‐resolution Raman‐induced Kerr effect spectra spanning a large vibrational range. Because it is a polarization detection technique, FRIKES produces background‐free Raman spectra with high signal‐to‐noise and rapid acquisition times. The practicality of FRIKES is demonstrated by obtaining Raman spectra of common solvents, revealing that its performance is comparable to femtosecond stimulated Raman spectroscopy (FSRS). The capabilities of FRIKES will make it a valuable new vibrational spectroscopic tool for studies of chemical and biological systems, especially once it is extended to time‐resolved studies.