Scattering induced spatial superpositions in multi-particle localization

TL;DR

This paper investigates how scattering processes induce the emergence of classical-like spatial configurations in multi-particle quantum systems, revealing the formation and robustness of superpositions during localization.

Contribution

It demonstrates that scattering can create and sustain quantum superpositions of particle positions, and shows how free evolution destroys these superpositions, leading to classical localization.

Findings

Superpositions of spatial configurations are formed during localization.

Scattering events do not cause decoherence of these superpositions.

Free evolution destroys superpositions, resulting in classical positions.

Abstract

We describe how quasiclassical relative positions of particles emerge in an initially delocalized quantum system as scattering of a probe beam is observed. We show that in the multiparticle case this localization in position space occurs via intermediate states that are quantum superpositions of spatial configurations. These superpositions are robust to consecutive scattering events, and scattering alone does not lead to their decoherence. Instead the free evolution of the system combines with scattering to destroy these superpositions, leading the particles to adopt classical-like positions relative to one another.