Work

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

Year: 2026

Type: article

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. For Bell-diagonal qutrit states with a Weyl structure, combining two existing results shows that violating the positive partial transpose (PPT) criterion is both necessary and sufficient for one-copy distillability. However, these results do not identify a Schmidt-rank-2 witness that maximizes robustness to white noise. To address this limitation, we present a noise-robust entanglement-distillation scheme for all non-PPT Bell-diagonal qutrit states with a Weyl structure. Specifically, we construct a Schmidt-rank-2 eigenvector of the partially transposed density matrix associated with its unique, threefold 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.

Source: Physical Review A

DOI: 10.1103/bgdw-3bln

Authors: Tobias C. Sutter, Christopher Popp, Beatrix C. Hiesmayr

Institutions: University of Vienna, Interdisciplinary Transformation University Austria

Language: English

Topic: Quantum Information and Cryptography

Subfield: Artificial Intelligence

Field: Computer Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $2,675

Funder: Austrian Science Fund