Related papers: Optimality of universal conclusive entanglement purification protocols

Optimality of universal conclusive entanglement purification protocols

URL: http://arxiv.org/abs/2509.09423v1
Date: Thu, 11 Sep 2025 13:04:17 GMT
Title: Optimality of universal conclusive entanglement purification protocols
Authors: Alexandre C. Orthey, Aby Philip, Tulja Varun Kondra, Alexander Streltsov,
Abstract summary: We establish fundamental limits for conclusive protocols distilling perfect Bell states from a pure two-qubit states.<n>We prove that a known protocol achieves these bounds, confirming its optimality.
Score: 75.52645767671567
License: http://creativecommons.org/licenses/by/4.0/
Abstract: Entanglement purification is essential for quantum technologies; yet, rigorous bounds on the success probability for universal protocols -- those requiring no prior knowledge about the input state -- have remained underexplored. We establish such fundamental limits for conclusive protocols distilling perfect Bell states from a pure two-qubit states by deriving the optimal success probability starting with: two copies of a state with known Schmidt basis, and four copies of a state with unknown Schmidt basis. We prove that a known protocol achieves these bounds, confirming its optimality. Crucially, universality imposes an inherent efficiency trade-off, yielding an average success probability of just $2/105$ over Haar measure.

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