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We performed pump-probe spectroscopy on OD stretching mode in KTaO3 to explore how a proton/deuteron interacts with the surroundings. We identified the potential anharmonicity and phonon modes which interact with a proton/deuteron, considering the temperature effect.

We demonstrate surface-enhanced ultrafast vibrational spectroscopy employing periodic arrays of infrared-resonant gold nanoantennas. The antenna-enhancements of molecular vibrational responses are analytically formulated with a simple coupled-dipole model, and the linear/nonlinear local signal enhancements are evaluated to be ~104and 107, respectively.

Coherent controls over vibrational excitations in metal di-carbonyls were demonstrated by using phase-shaped mid-infrared pulses. The phase of the inter-state coherence between two different normal-modes was controlled by changing the phase step of the stepwise spectral phase profile. The quantum interference between multiple vibrational excitation paths in resonant two-step excitations was manipulated by the similar spectral phase control. The results experimentally confirmed that coherent control over multiple vibrational degrees of freedom works properly in condensed phases. There remains the possibility for increasing excitation efficiency by introducing group-delays and by optimizing polarization state of the excitation pulse.