Closing a single-copy gap to the Holevo bound with two-copy measurements

arXiv:2609.36874 · quant-ph · Submitted 2026-09-29 · Read on arXiv

quant-ph

Submitted: 2026-09-29

Updated: 2026-09-29

Terminology

• Fisher Information — 18× in this paper · explained in 3 episodes
• Trace — 15× in this paper · explained in 2 episodes
• Hilbert Space — 12× in this paper · explained in 2 episodes
• Calibration — 9× in this paper · explained in 7 episodes
• Additivity — 2× in this paper · explained in 1 episode
• Consistency — 1× in this paper · explained in 3 episodes
• Kernel decomposition — 1× in this paper · explained in 2 episodes
• Reconstruction Error — 1× in this paper · explained in 2 episodes
• Regularization — 1× in this paper · explained in 3 episodes
• Semidefinite Program (SDP) — 1× in this paper · explained in 2 episodes

Sources

• A geometric perspective: experimental evaluation of the quantum Cramer-Rao bound
• Control incompatibility in multiparameter quantum metrology
• The gap persistence theorem for quantum multiparameter estimation
• Attainability of the Holevo-Cram'er-Rao bound for two-qubit 3D magnetometry

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