0000000001120123
AUTHOR
Haisu Zhang
showing 2 related works from this author
Ultrafast collisional dissipation of symmetric-top molecules probed by rotational alignment echoes
2020
We experimentally and theoretically investigate the ultrafast collisional dynamics of a symmetric-top molecule (${\mathrm{C}}_{2}{\mathrm{H}}_{6}$) in pure gas and mixtures with He at high density by employing the rotational alignment echo created by a pair of time-delayed intense laser kicks. The decrease of the amplitude of the echo when increasing the delay between the two laser pulses, reflecting the collisional relaxation of the system, is measured by probing the transient birefringence induced in the medium. The theoretical predictions, carried using purely classical molecular dynamics simulations, reproduce well the observed features, as demonstrated previously for a linear molecule.…
Rotational echoes as a tool for investigating ultrafast collisional dynamics of molecules
2019
We show that recently discovered rotational echoes of molecules provide an efficient tool for studying collisional molecular dynamics in high-pressure gases. Our study demonstrates that rotational echoes enable the observation of extremely fast collisional dissipation, at timescales of the order of a few picoseconds, and possibly shorter. The decay of the rotational alignment echoes in ${\mathrm{CO}}_{2}$ gas and ${\mathrm{CO}}_{2}\text{\ensuremath{-}}\mathrm{He}$ mixture up to 50 bar was studied experimentally, delivering collision rates that are in good agreement with the theoretical expectations. The suggested measurement protocol may be used in other high-density media, and potentially …