Quantum Brain
← Back to papers

Enhancing Quantum Metrology with High-order Fisher Information and Experiments

Xin-Zhu Liu, Jun-Li Jiang, Yan-Han Yang, Li-Ming Zhao, Xue Yang, Shao-Ming Fei, Ming-Xing Luo·June 26, 2026
Quantum Physics

AI Breakdown

Get a structured breakdown of this paper — what it's about, the core idea, and key takeaways for the field.

Abstract

Fisher information plays a central role in statistics and quantum metrology, providing the basis for the celebrated Cramér-Rao bound. In this work, we introduce a new information measure based on higher-order Fisher information and show that it naturally leads to a generalized uncertainty relation for parameter estimation, which can be regarded as an extension of the Cramér-Rao bound. As an application, we analyze the case of quantum phase estimation with a single qubit and compare our theoretical bounds with the well-known established hierarchical bounds. Finally, we experimentally validate the proposed framework using a photonic platform.

Related Research

Quantum Intelligence

Ask about quantum research, companies, or market developments.