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arXiv · 2604.24460

Noise-robust 1-copy distillation protocol for all distillable Bell-diagonal qutrits

Tobias C. Sutter·Christopher Popp·Beatrix C. Hiesmayr
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Abstract

Entanglement distillation is the process of converting noisy entangled states into maximally entangled pure states via local operations and classical communication. A long-standing, unresolved question is which entangled states are amenable to distillation, known as the distillability problem. We solve this for Bell-diagonal qutrits with Weyl structure, and present a noise-robust scheme for entanglement distillation. In particular, we find that violating the positive partial transposition (PPT) criterion is necessary and sufficient for the 1-distillability of these states. For this, we construct a Schmidt rank 2 eigenvector of the partially transposed density matrix associated with its unique, three-fold degenerate negative eigenvalue. This feature makes the derived entanglement distillation protocol resilient to white-noise effects on the quantum states. Our results thus make noisy entangled qutrit pairs more accessible for future quantum technologies.

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Tobias C. Sutter, Christopher Popp, Beatrix C. Hiesmayr. 2026-04-27. Noise-robust 1-copy distillation protocol for all distillable Bell-diagonal qutrits. https://arxiv.org/abs/2604.24460

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