Operational determination of multi-qubit entanglement classes via tuning of local operations

TL;DR

This paper introduces a physical setup that enables the generation of arbitrary symmetric multiqubit entangled states, including GHZ and W states, by tuning local operations, and establishes a direct link between experimental parameters and entanglement classes.

Contribution

It provides a method to produce and classify symmetric multiqubit entangled states through local tuning of polarizer orientations, with a focus on three-qubit states.

Findings

One-to-one correspondence between polarizer settings and entanglement classes.

Ability to produce arbitrary symmetric multiqubit entangled states.

Experimental parameters directly determine the entanglement class.

Abstract

We present a physical setup with which it is possible to produce arbitrary symmetric long-lived multiqubit entangled states in the internal ground levels of photon emitters, including the paradigmatic GHZ and W states. In the case of three emitters, where each tripartite entangled state belongs to one of two well-defined entanglement classes, we prove a one-to-one correspondence between well-defined sets of experimental parameters, i.e., locally tunable polarizer orientations, and multiqubit entanglement classes inside the symmetric subspace.