Controlling the Ultrafast Dynamics of HD⁺ by the Carrier-Envelope Phases of an Ultrashort Laser Pulse: A Quasi-Classical Dynamics Study

Abstract

A theoretical study on the coupled electron-nuclear dynamics of HD + molecular ion under ultrashort, intense laser pulses is performed by employing a well-established quasiclassical model. The influence of laser carrier-envelope phase on various channel (H+D + , D+H + and H + +D + ) probabilities is investigated at different laser field intensities. The carrier envelope phase is found to govern the dissociation (H+D + and D+H + ) and Coulomb explosion channel (H + +D + ) probabilities. The kinetic energy release distributions of the fragments are also found to be sensitive to the carrier-envelope phase of the laser pulse. Our results are in agreement with the previously reported quantum dynamical studies and experiments.

Strong Laser Field-Driven Coupled Electron–Nuclear Dynamics: Quantum vs Classical Description

“…Note that we have not considered the double-ionization channel [H 2 + + n ℏω → H 2 2+ + e] , in our dynamical calculations since it had previously been observed that after long time of propagation, this channel eventually explodes to form the Coulomb explosion products. It is worth to mention that by employing quasi-classical trajectory methods, the double-ionization channel can be properly counted when the diatomic bond length r bc < 9.5 bohr and the electron energy ε i > 0.…”

“…We have employed a quasi-classical method based on Heisenberg’s model potential, which is quite well tested − and has already been implemented in some of our previous studies on HD + and H 2 molecules. , Presently, we apply this model to a H 2 + molecular ion, which is a three-particle system consisting of two nuclei and one electron. The quasi-classical model is based on the Hamiltonian formulation of the classical mechanics, where the most crucial step is to define a total molecular Hamiltonian.…”

“…For such a three-particle system consisting of two nuclei and one electron, both quantum and classical methods have been applied to study the dynamics with the inclusion of both electronic and nuclear degrees of freedom to exactly simulate the CEP-dependent strong field experiments. In our previous studies, we have used the classical dynamical approach to study one- and two-electron isotopomers, ,, which were compared with the experimental measurements. However, the principal aim of this study is to compare both quantum and classical methodologies under exact similar initial conditions, which is extremely important to benchmark the classical model.…”

Dissociative ionization of the H2 molecule under a strong elliptically polarized laser field: carrier-envelope phase and orientation effect

“…The auxiliary potentials were first introduced by Kirschbaum and Wilets 40,41 and later, further developments were carried out by Cohen. 42 The model has been used extensively to study laser-driven atomic and molecular processes, 38,43–47 as well as atom–ion collision processes. 48…”

“…The auxiliary potentials were first introduced by Kirschbaum and Wilets 40,41 and later, further developments were carried out by Cohen. 42 The model has been used extensively to study laser-driven atomic and molecular processes, 38,[43][44][45][46][47] as well as atom-ion collision processes. 48 The field-free Hamiltonian of the H 2 molecule in the quasiclassical model is given by eqn (1) (atomic units are used throughout unless stated otherwise):…”