Entanglement detection in the vicinity of arbitrary Dicke states

TL;DR

This paper introduces an experimentally feasible method to detect genuine multipartite entanglement near arbitrary Dicke states, requiring only three collective spin measurements, and effective even with low fidelity in large systems.

Contribution

It presents a novel detection scheme for multipartite entanglement around Dicke states that is simple to implement and robust against fidelity loss.

Findings

Detects genuine multipartite entanglement near Dicke states

Requires only three collective spin measurements

Effective even when state fidelity decreases exponentially

Abstract

Dicke states represent a class of multipartite entangled states that can be generated experimentally with many applications in quantum information. We propose a method to experimentally detect genuine multipartite entanglement in the vicinity of arbitrary Dicke states. The detection scheme can be used to experimentally quantity the entanglement depth of many-body systems and is easy to implement as it requires to measure only three collective spin operators. The detection criterion is strong as it heralds multipartite entanglement even in cases where the state fidelity goes down exponentially with the number of qubits.