Molecular symmetry effects in the ionization of CS$_2$ by intense, few-cycle laser pulses

TL;DR

This study demonstrates that molecular symmetry significantly influences ionization processes in CS₂ when using intense, few-cycle laser pulses, revealing suppression of rescattering and dissociation due to quantum interference effects.

Contribution

It provides experimental evidence that molecular symmetry affects strong field ionization and rescattering suppression in CS₂ with ultrashort laser pulses.

Findings

Rescattering is effectively switched off with few-cycle pulses.

Dissociation channels are suppressed, favoring charged molecular ions.

Quantum-mechanical symmetry influences ionization dynamics.

Abstract

Few-cycle pulses of intense 800 nm light are used to probe ionization and dissociation of carbon disulfide in the intensity and temporal regime where rescattering is expected to dominate the laser-molecule interaction. The wavepacket of the rescattered electron destructively interferes with the anti-bonding $\pi$-orbital of CS$_2^+$ such that rescattering is effectively "switched off". Direct signature of enhanced ionization being "switched off" in the ultrashort domain is also obtained. Consequently, dissociation becomes an almost non-existent channel when few-cycle pulses are used, with only long-lived singly-, doubly-, and triply-charged molecular ions dominating the mass spectrum. Few-cycle optical pulses help reveal that quantum-mechanically determined molecular symmetry contributes to strong field molecular ionization.