Molecular orientation echoes via concerted terahertz and near-IR excitations

A new and efficient method for orientation echo spectroscopy is presented and realized experimentally. The excitation scheme utilizes concerted rotational excitations by both ultrashort terahertz and near-IR pulses and its all-optical detection is enabled by the molecular orientation-induced second harmonic method [J. Phys. Chem. A 126 , 3732 (2022)]. This method provides practical means for orientation echo spectroscopy of gas phase molecules and highlights the intriguing underlying physics of coherent rotational dynamics induced by judiciously-orchestrated interactions with both resonant (terahertz) and nonresonant (NIR) fields.(c) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Automated summary

A new and efficient method for orientation echo spectroscopy, utilizing concerted rotational excitations by both ultrashort terahertz and near-IR pulses, is presented and experimentally realized in this study. The all-optical detection is enabled by the molecular orientation-induced second harmonic method. This method provides practical means for investigating the orientation echo spectroscopy of gas phase molecules and highlights the intriguing underlying physics of coherent rotational dynamics induced by judiciously-orchestrated interactions with both resonant and nonresonant fields.