Monday, December 21, 2015
Abstract-Nonlinear terahertz coherent excitation of vibrational modes of liquids
We report the first excitation of intramolecular vibrational modes via the nonlinear interaction of a TeraHertz (THz) light field with molecular liquids. A terahertz-terahertz-Raman pulse sequence prepares the with a broadband, high-energy, (sub)picosecond terahertz pulse, that are then measured in a terahertz spectrometer via phase-sensitive, with an optical pulse. The spectrometer reported here has broader terahertz frequency coverage, and an increased sensitivity relative to previously reported terahertz experiments. Vibrational are observed in liquid diiodomethane at 3.66 THz (122 cm−1), and in carbon tetrachloride at 6.50 THz (217 cm−1), in exact agreement with literature values of those intramolecular modes. This work opens the door to 2D nonlinear in terahertz field, that can study the of condensed-phase molecular systems, as well as control at terahertz frequencies.