2021/03/31 by A. Altherr, Anian Altherr, Yuxiang Yang
Computer Science · Mathematics · Physics and Astronomy · #Computability, Logic, AI Algorithms #Computer science #Markov process #Mathematics #Metrology #Open quantum system #Physics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum channel #Quantum error correction #Quantum information #Quantum mechanics #Quantum metrology #Quantum sensor #Quantum state #Quantum technology #Statistical physics #Statistics #quant-ph
paper · pdf · doi:10.1103/physrevlett.127.060501
published as Phys. Rev. Lett. 127, 060501 (2021) · 5 pages, 6 figures + appendix; published version
openalex publication_date 2021/08/02 · arxiv created 2021/08/03 · arxiv updated 2021/08/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Quantum metrology is a rapidly developing branch of quantum technologies. While various theories have been established on quantum metrology for Markovian processes, i.e., quantum channel estimation, quantum metrology for non-Markovian processes is much less explored. In this Letter, we establish a general framework of non-Markovian quantum metrology. For any parametrized non-Markovian process on a finite-dimensional system, we derive a formula for the maximal amount of quantum Fisher information that can be extracted from it by an optimally controlled probe state. In addition, we design an algorithm that evaluates this quantum Fisher information via semidefinite programming. We apply our framework to noisy frequency estimation, where we find that the optimal performance of quantum metrology is better in the non-Markovian scenario than in the Markovian scenario and explore the possibility of efficient sensing via simple variational circuits.