Work

Number of bits returned by a quantum estimation

Year: 2024

Type: article

Abstract: We give two upper bounds to the mutual information in arbitrary quantum estimation strategies. The first is based on some simple Fourier properties of the estimation apparatus. The second is derived using the first, but, interestingly, depends only on the Fisher information of the parameter, so it is valid even beyond quantum estimation. We illustrate the usefulness of these bounds by characterizing the quantum phase estimation algorithm in the presence of noise. In addition, for the noiseless case, we extend the analysis beyond applying the bound and we discuss the optimal entangled and adaptive strategies, clarifying inaccuracies appearing on this topic in the literature.

Source: Physical Review A

DOI: 10.1103/physreva.110.032405

Authors: Xi Lu, Wojciech Górecki, Chiara Macchiavello, Lorenzo Maccone

Institutions: Zhejiang University, Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, University of Pavia

Language: English

Topic: Quantum Information and Cryptography

Subfield: Artificial Intelligence

Field: Computer Science

Domain: Physical Sciences

Open Access status: green

Funders: U.S. Department of Energy, National Natural Science Foundation of China, Ministero dell'Università e della Ricerca