Quantum motion with trajectories: beyond the Gaussian beam approximation

TL;DR

This paper introduces a quantum model using a variational approach that describes particle trajectories beyond Gaussian beam approximation, improving the simulation of nearly localized quantum particles like light nuclei.

Contribution

It presents a novel variational method for quantum particle trajectories that extends beyond Gaussian beam approximation, connecting with Bohmian trajectories.

Findings

Provides a new trajectory-based quantum simulation method.

Shows improved accuracy for nearly localized particles.

Establishes links with Bohm trajectories approach.

Abstract

A quantum model based on a Euler-Lagrange variational approach is proposed. In analogy with the classical transport, our approach maintain the description of the particle motion in terms of trajectories in a configuration space. Our method is designed to describe correction to the motion of nearly localized particles due to quantum phenomena. We focus on the simulation of the motion of light nuclei in ab initio calculations. Similarly to the Gaussian beam method, our approach is based on a ansatz for the particle wave function. We discuss the completeness of our ansatz and the connection of our results with the Bohm trajectories approach.