Nonadiabatic quantum dynamics without potential energy surfaces
Abstract
We present an ab initio algorithm for quantum dynamics simulations that reformulates the traditional "curse of dimensionality" that plagues all stateoftheart techniques for solving the timedependent Schrödinger equation. Using a stochastic wavefunction ansatz that is based on a set of interacting singleparticle conditional wave functions, we show that the difficulty of the problem becomes dominated by the number of trajectories needed to describe the process, rather than simply the number of degrees of freedom involved. This highly parallelizable technique achieves quantitative accuracy for situations in which meanfield theory drastically fails to capture qualitative aspects of the dynamics, such as quantum decoherence or the reduced nuclear probability density, using orders of magnitude fewer trajectories than a meanfield simulation. We illustrate the performance of this method for two fundamental nonequilibrium processes: a photoexcited protoncoupled electron transfer problem, and nonequilibrium dynamics in a cavity bound electronphoton system in the ultrastrongcoupling regime.
 Publication:

Physical Review Materials
 Pub Date:
 February 2019
 DOI:
 10.1103/PhysRevMaterials.3.023803
 arXiv:
 arXiv:1805.11169
 Bibcode:
 2019PhRvM...3b3803A
 Keywords:

 Condensed Matter  Mesoscale and Nanoscale Physics;
 Physics  Chemical Physics
 EPrint:
 Phys. Rev. Materials 3, 023803 (2019)