Optimization of the Femtosecond Laser Impulse for Excitation and the Spin-Orbit Mediated Dissociation in the NaRb Dimer

TL;DR

This paper investigates how femtosecond laser pulses can be optimized to excite NaRb dimers and induce spin-orbit mediated dissociation, providing insights into population dynamics and optimal control strategies for molecular state manipulation.

Contribution

It introduces a method to optimize femtosecond laser parameters for maximum excitation and controlled dissociation of NaRb dimers, including analysis of population oscillations and decay behaviors.

Findings

Optimized laser parameters yield maximum population in excited states.

Identified power-law decay in state populations.

Determined optimal timing for molecular ground state transfer.

Abstract

We study the dynamics of multiple coupled states under the influence of an arbitrary time-dependent external field to investigate the femtosecond laser-driven excitation and the spin-orbit mediated dissociation in the NaRb dimer. In this process, the dimer is excited from the ground triplet state $1^3\Sigma^+$ to the $1^3\Pi$ state using the femtosecond laser impulse and the spin-orbit coupling between the $1^3\Pi$ and $2^1\Sigma^+$ states results in the singlet-triplet transition. The laser impulse parameters are optimised to obtain maximum yield in electronic states correlating with the first excited atomic asymptote. We observe the detailed population statistics and power-law decay of these states. Finally, the analysis of the population oscillations allows us to determine the optimal time delay for dumping the molecule to its absolute ground state.