Quantum discord determines the interferometric power of quantum states
Quantum metrology exploits quantum mechanical laws to improve the precision in estimating technologically relevant parameters such as phase, frequency, or magnetic fields. Probe states are usually tailored to the particular dynamics whose parameters are being estimated. Here we consider a novel fram...
| Main Authors: | , , , , , , , , |
|---|---|
| Format: | Article |
| Published: |
American Physical Society
2014
|
| Online Access: | https://eprints.nottingham.ac.uk/47216/ |
| _version_ | 1848797492134543360 |
|---|---|
| author | Girolami, Davide Souza, Alexandre M. Giovannetti, Vittorio Tufarelli, Tommaso Filgueiras, Jefferson G. Sarthour, Roberto S. Soares-Pinto, Diogo O. Oliveira, Ivan S. Adesso, Gerardo |
| author_facet | Girolami, Davide Souza, Alexandre M. Giovannetti, Vittorio Tufarelli, Tommaso Filgueiras, Jefferson G. Sarthour, Roberto S. Soares-Pinto, Diogo O. Oliveira, Ivan S. Adesso, Gerardo |
| author_sort | Girolami, Davide |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | Quantum metrology exploits quantum mechanical laws to improve the precision in estimating technologically relevant parameters such as phase, frequency, or magnetic fields. Probe states are usually tailored to the particular dynamics whose parameters are being estimated. Here we consider a novel framework where quantum estimation is performed in an interferometric configuration, using bipartite probe states prepared when only the spectrum of the generating Hamiltonian is known. We introduce a figure of merit for the scheme, given by the worst-case precision over all suitable Hamiltonians, and prove that it amounts exactly to a computable measure of discord-type quantum correlations for the input probe. We complement our theoretical results with a metrology experiment, realized in a highly controllable room-temperature nuclear magnetic resonance setup, which provides a proof-of-concept demonstration for the usefulness of discord in sensing applications. Discordant probes are shown to guarantee a nonzero phase sensitivity for all the chosen generating Hamiltonians, while classically correlated probes are unable to accomplish the estimation in a worst-case setting. This work establishes a rigorous and direct operational interpretation for general quantum correlations, shedding light on their potential for quantum technology. |
| first_indexed | 2025-11-14T20:04:44Z |
| format | Article |
| id | nottingham-47216 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| last_indexed | 2025-11-14T20:04:44Z |
| publishDate | 2014 |
| publisher | American Physical Society |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-472162020-05-04T16:47:35Z https://eprints.nottingham.ac.uk/47216/ Quantum discord determines the interferometric power of quantum states Girolami, Davide Souza, Alexandre M. Giovannetti, Vittorio Tufarelli, Tommaso Filgueiras, Jefferson G. Sarthour, Roberto S. Soares-Pinto, Diogo O. Oliveira, Ivan S. Adesso, Gerardo Quantum metrology exploits quantum mechanical laws to improve the precision in estimating technologically relevant parameters such as phase, frequency, or magnetic fields. Probe states are usually tailored to the particular dynamics whose parameters are being estimated. Here we consider a novel framework where quantum estimation is performed in an interferometric configuration, using bipartite probe states prepared when only the spectrum of the generating Hamiltonian is known. We introduce a figure of merit for the scheme, given by the worst-case precision over all suitable Hamiltonians, and prove that it amounts exactly to a computable measure of discord-type quantum correlations for the input probe. We complement our theoretical results with a metrology experiment, realized in a highly controllable room-temperature nuclear magnetic resonance setup, which provides a proof-of-concept demonstration for the usefulness of discord in sensing applications. Discordant probes are shown to guarantee a nonzero phase sensitivity for all the chosen generating Hamiltonians, while classically correlated probes are unable to accomplish the estimation in a worst-case setting. This work establishes a rigorous and direct operational interpretation for general quantum correlations, shedding light on their potential for quantum technology. American Physical Society 2014-05-27 Article PeerReviewed Girolami, Davide, Souza, Alexandre M., Giovannetti, Vittorio, Tufarelli, Tommaso, Filgueiras, Jefferson G., Sarthour, Roberto S., Soares-Pinto, Diogo O., Oliveira, Ivan S. and Adesso, Gerardo (2014) Quantum discord determines the interferometric power of quantum states. Physical Review Letters, 112 (21). 210401-1-210401-5. ISSN 1079-7114 https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.112.210401 doi:10.1103/PhysRevLett.112.210401 doi:10.1103/PhysRevLett.112.210401 |
| spellingShingle | Girolami, Davide Souza, Alexandre M. Giovannetti, Vittorio Tufarelli, Tommaso Filgueiras, Jefferson G. Sarthour, Roberto S. Soares-Pinto, Diogo O. Oliveira, Ivan S. Adesso, Gerardo Quantum discord determines the interferometric power of quantum states |
| title | Quantum discord determines the interferometric power of quantum states |
| title_full | Quantum discord determines the interferometric power of quantum states |
| title_fullStr | Quantum discord determines the interferometric power of quantum states |
| title_full_unstemmed | Quantum discord determines the interferometric power of quantum states |
| title_short | Quantum discord determines the interferometric power of quantum states |
| title_sort | quantum discord determines the interferometric power of quantum states |
| url | https://eprints.nottingham.ac.uk/47216/ https://eprints.nottingham.ac.uk/47216/ https://eprints.nottingham.ac.uk/47216/ |