Coherent Ro-vibrational Revivals in a Thermal Molecular Ensemble

TL;DR

This paper explores the evolution of vibrational coherence in nitrogen molecules, revealing new ro-vibrational revival phenomena and enabling precise measurement of molecular constants through advanced spectroscopic techniques.

Contribution

It presents the first combined experimental and theoretical analysis of ro-vibrational revivals in a thermal molecular ensemble, highlighting new control possibilities for decoherence.

Findings

Detection of rotational dephasing and rephasing of vibrational coherence.

Observation of full and fractional ro-vibrational revivals.

Determination of the second-order ro-vibrational constant gamma_e.

Abstract

We report an experimental and theoretical study of the evolution of vibrational coherence in a thermal ensemble of nitrogen molecules. Rotational dephasing and rephasing of the vibrational coherence is detected by coherent anti-Stokes Raman scattering. The existence of ro-vibrational coupling and the discrete energy spectrum of the rotational bath lead to a whole new class of full and fractional ro-vibrational revivals. Following the rich ro-vibrational dynamics on a nanosecond time scale with sub-picosecond time resolution enables us to determine the second-order ro-vibrational constant $gamma_e$ and assess new possibilities of controlling decoherence.