Coupled forward-backward trajectory approach for non-equilibrium electron-ion dynamics

Abstract

We introduce a simple ansatz for the wavefunction of a many-body system based on coupled forward and backward-propagating semiclassical trajectories. This method is primarily aimed at, but not limited to, treating nonequilibrium dynamics in electron-phonon systems. The time-evolution of the system is obtained from the Euler-Lagrange variational principle, and we show that this ansatz yields Ehrenfest mean field theory in the limit that the forward and backward trajectories are orthogonal, and in the limit that they coalesce. We investigate accuracy and performance of this method by simulating electronic relaxation in the spin-boson model and the Holstein model. Although this method involves only pairs of semiclassical trajectories, it shows a substantial improvement over mean field theory, capturing quantum coherence of nuclear dynamics as well as electron-nuclear correlations. This improvement is particularly evident in nonadiabatic systems, where the accuracy of this coupled trajectory method extends well beyond the perturbative electron-phonon coupling regime. This approach thus provides an attractive route forward to the ab-initio description of relaxation processes, such as thermalization, in condensed phase systems.

References in corpus (9)

• Resolving photon number states in a superconducting circuit
• An optically stimulated superconducting-like phase in K3C60 far above equilibrium Tc
• A coupled-trajectory quantum-classical approach to decoherence in non-adiabatic processes
• Approximate but Accurate Quantum Dynamics from the Mori Formalism: I. Nonequilibrium Dynamics
• Polaron dynamics with a multitude of Davydov D${}_2$ trial states
• Real-time decay of a highly excited charge carrier in the one-dimensional Holstein model
• Accurate nonadiabatic quantum dynamics on the cheap: making the most of mean field theory with master equations
• Ab initio simulations of excited carrier dynamics in carbon nanotubes
• Approximate but accurate quantum dynamics from the Mori formalism: II. Equilibrium correlation functions

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