Towards controlling the dissociation probability by light-induced conical intersections

TL;DR

This paper explores controlling molecular dissociation by manipulating light-induced conical intersections (LICIs) with specially designed chirped laser pulses to influence the dissociation dynamics of D₂⁺.

Contribution

It introduces a method to steer the LICI position using tailored chirped pulses, aiming to enhance control over molecular dissociation processes.

Findings

Chirped pulses can move LICIs in sync with vibrational wave packets.

Controlling LICIs impacts dissociation probabilities.

Population distributions of vibrational levels are affected by LICI manipulation.

Abstract

Light-induced conical intersections (LICIs) can be formed both by standing or by running laser waves. The position of a LICI is determined by the laser frequency while the laser intensity controls the strength of the nonadiabatic coupling. Recently, it was shown within the LICI framework that linearly chirped laser pulses have an impact on the dissociation dynamics of the $D_{2}^{+}$ molecule (J. Chem. Phys. 143, 014305, (2015); ibid 144, 074309, (2016)). In this work we exploit this finding and perform calculations using chirped laser pulses in which the time dependence of the laser frequency is designed so as to force the LICI to move together with the field-free vibrational wave packet as much as possible. Since nonadiabaticity is strongest in the vicinity of the conical intersection, this is the first step towards controlling the dissociation process via the LICI. Our showcase example is again the $D_{2}^{+}$ molecular ion. To demonstrate the impact of the LICIs on the dynamical properties of diatomics, the total dissociation probabilities and the population of the different vibrational levels after the dissociation process are studied and discussed.