From quantum to classical description of intense laser-atom physics with Bohmian trajectories

摘要

In this paper, Bohmian mechanics is introduced to the intense laser-atomphysics. The motion of atomic electron in intense laser field is obtained fromthe Bohm-Newton equation. We find the quantum potential that dominates thequantum effect of a physical system becomes negligible as the electron isdriven far away from the parent ion by the intense laser field, i.e. thebehavior of the electron smoothly trends to be classical soon after theelectron was ionized. Our numerical calculations present a direct positiveevidence for the semiclassical trajectory methods in the intense laser-atomphysics where the motion of the ionized electron is treated by the classicalmechanics, while quantum mechanics is needed before the ionization.