Libration induced stretching mode excitation for pump-probe spectroscopy in pure liquid water

Femtosecond 2DIR spectroscopy of the nitrile stretching vibration of thiocyanate anions in liquid-to-supercritical heavy water. Spectral diffusion and libration-induced hydrogen-bond dynamics.

Femtosecond two-dimensional infrared (2DIR) spectroscopy was carried out to study the dynamics of vibrational spectral diffusion of the nitrile stretching vibration of thiocyanate anions (S-C≡N(-)) dissolved in liquid-to-supercritical heavy water (D2O). The 2DIR line shapes were used to extract through a nodal slope analysis quantitative information about the correlation function for temporal f...

Ground State Wavepackets in Pump-Probe Spectroscopy

We discuss the pump-probe signals expected from ground state wavepackets. The concept of a 'pure hole' is examined. The temporal form of the signals can be qualitatively predicted from the pump and probe wavelengths and pulse durations using the classical Franck principle. Temperature is found to play an important role. These considerations are illustrated with quant urn mechanical calculations...

Resonant uv pump-probe spectroscopy of dipicolinic acid via impulsive excitation

We present experimental evidence of coherent wave packet motion in dipicolinic acid C7H5NO4 which is an important marker molecule for bacterial spores. Resonant impulsive excitation is achieved by applying a uv pump pulse 267 nm, 16 fs which has a duration that is shorter than the vibrational period of the molecules. The resulting dynamics is then probed with a weaker pulse of the same width an...

Femtosecond real-time pump–probe imaging spectroscopy

Sagnac lnterferometry for Background Subtraction in Pump-Probe Spectroscopy

We describe a novel pump-probe optical method, based on a Sagnac (anti-resonant ring) interferometer, which removes over 99% of the DC background light inherent in normal, two beam pump-probe measurements. Suppression of the DC component is critical for pumpprobe imaging applications. In addition, this method greatly increases the signal-to-noise ratio compared with normal, two beam pump-probe ...