Optimal Verification of Greenberger-Horne-Zeilinger States
Optimal Verification of Greenberger-Horne-Zeilinger States
We construct optimal protocols for verifying qubit and qudit GHZ states using local projective measurements. When the local dimension is a prime, an optimal protocol is constructed from Pauli measurements only. Our protocols provide a highly efficient way for estimating the fidelity and certifying genuine multipartite entanglement. In particular, they …