Adiabatic and Nonadiabatic Dynamics with Interacting Quantum Trajectories.

Area of Science:

• Quantum mechanics
• Computational chemistry
• Theoretical physics

Background:

• Traditional quantum dynamics methods often rely on wavefunctions, which can be computationally intensive.
• Describing both adiabatic and nonadiabatic processes within a single framework remains a challenge.
• Existing methods for quantum dynamics without wavefunctions have limitations.

Purpose of the Study:

• To develop a unified quantum dynamics method capable of describing both adiabatic and nonadiabatic processes.
• To introduce a stable and accurate numerical scheme for quantum trajectory propagation.
• To explore an alternative to wavefunction-based methods in quantum dynamics.

Main Methods:

• A quantum dynamics method based on the propagation of interacting quantum trajectories.
• Determining the quantum force from Bohmian hydrodynamic formulation using trajectory information.
• A time-dependent propagation scheme for enhanced stability.
• Combination with the exact factorization method for nonadiabatic regimes.

Main Results:

• The proposed method successfully describes both adiabatic and nonadiabatic quantum dynamics.
• The time-dependent propagation scheme demonstrates very stable dynamics.
• The method's performance is validated on analytical potentials and in nonadiabatic scenarios.

Conclusions:

• The interacting quantum trajectory method offers a robust and unified approach to quantum dynamics.
• This wavefunction-free formalism provides a stable and efficient alternative for complex quantum systems.
• The method shows promise for simulating a wide range of quantum phenomena.