Quantum-classical nonadiabatic dynamics of Floquet driven systems

TL;DR

This paper introduces a trajectory-based quantum-classical method combining exact factorization and Floquet formalism to simulate nonadiabatic molecular dynamics under periodic external drives, enabling efficient modeling of driven molecular systems.

Contribution

It develops a novel algorithm integrating Floquet theory with trajectory-based dynamics for nonadiabatic systems under periodic driving, extending existing mixed quantum-classical approaches.

Findings

Algorithm successfully applied to a solvable model system.

Accurately captures nonadiabatic effects in driven molecular dynamics.

Demonstrates effectiveness across different field intensities.

Abstract

We develop a trajectory-based approach for excited-state molecular dynamics simulations of systems subject to an external periodic drive. We combine the exact-factorization formalism, allowing to treat electron-nuclear systems in nonadiabatic regimes, with the Floquet formalism for time-periodic processes. The theory is developed starting with the molecular time-dependent Schroedinger equation with inclusion of an external periodic drive that couples to the system dipole moment. With the support of the Floquet formalism, quantum dynamics is approximated by combining classical-like, trajectory-based, nuclear evolution with electronic dynamics represented in the Floquet basis. The resulting algorithm, which is an extension of the coupled-trajectory mixed quantum-classical scheme for periodically driven systems, is applied to a model study, exactly solvable, with different field intensities.