Physical Review A
Criterion for testing multiparticle negative-partial-transpose entanglement
Bei Zeng, Di Zhou, Peng Zhang, Zhen‐Peng Xu, Lixing You
Abstract
We revisit the criterion of multiparticle entanglement based on the overlaps of a given quantum state $\ensuremath{\rho}$ with maximally entangled states. For a system of m particles, each with N distinct states, we prove that $\ensuremath{\rho}$ is m-particle negative partial transpose entangled, if there exists a maximally entangled state $|\mathrm{MES}〉,$ such that $〈\mathrm{MES}|\ensuremath{\rho}|\mathrm{MES}〉>1/N.$ While this sufficiency condition is weaker than the Peres-Horodecki criterion in all cases, it applies to multi-particle systems, and becomes especially useful when the number of particles (m) is large. We also consider the converse of this criterion and illustrate its invalidity with counter examples.