Entanglement Generation by Qubit Scattering in Three Dimensions

TL;DR

This paper investigates how a scattered qubit can generate entanglement between two fixed target qubits in three dimensions, analyzing the process in detail to identify conditions for high-quality entanglement.

Contribution

It provides a detailed 3D analysis of qubit scattering and its role in entanglement generation, including perturbative and renormalized approaches, with practical insights into optimizing entanglement quality.

Findings

Entanglement depends on scattering angles and wave packet size.

High-quality entanglement is achievable under specific scattering conditions.

The analysis clarifies the role of path distinguishability in entanglement formation.

Abstract

A qubit (a spin-1/2 particle) prepared in the up state is scattered by local spin-flipping potentials produced by the two target qubits (two fixed spins), both prepared in the down state, to generate an entangled state in the latter when the former is found in the down state after scattering. The scattering process is analyzed in three dimensions, both to lowest order and in full order in perturbation, with an appropriate renormalization for the latter. The entanglement is evaluated in terms of the concurrence as a function of the incident and scattering angles, the size of the incident wave packet, and the detector resolution, to clarify the key elements for obtaining an entanglement with high quality. The characteristics of the results are also discussed in the context of (in)distinguishability of alternative paths for a quantum particle.