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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Uncertainty inequalities as entanglement criteria for negative partial-transpose States
Hyunchul Nha1, M Suhail Zubairy
1Department of Physics, Texas A & M University at Qatar, Doha, Qatar. hyunchul.nha@qatar.tamu.edu
Abstract:
In this Letter, we show that the fulfillment of uncertainty relations is a sufficient criterion for a quantum-mechanically permissible state. We specifically construct two pseudospin observables for an arbitrary nonpositive Hermitian matrix whose uncertainty relation is violated. This method enables us to systematically derive separability conditions for all negative partial-transpose states in experimentally accessible forms. In particular, generalized entanglement criteria are derived from the Schrödinger-Robertson inequalities for bipartite continuous-variable states.
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