Experimental Detection of Entanglement Polytopes via Local Filters

TL;DR

This paper demonstrates an experimental method to detect and distinguish entanglement types in a four-qubit system by combining entanglement polytopes with local filters, overcoming limitations of single-particle spectra analysis.

Contribution

It introduces the use of local filters to enhance entanglement polytope detection, enabling differentiation of states with identical spectra but different entanglement types.

Findings

Successful experimental detection of entanglement polytopes.

Local filters distinguish states with same spectra but different entanglement.

Method improves entanglement classification accuracy.

Abstract

Entanglement polytopes result in finitely many types of entanglement that can be detected by only measuring single-particle spectra. With high probability, however, the local spectra lie in more than one polytope, hence providing no information about the entanglement type. To overcome this problem, we propose to additionally use local filters. We experimentally demonstrate the detection of entanglement polytopes in a four-qubit system. Using local filters we can distinguish the entanglement type of states with the same single particle spectra, but which belong to different polytopes.