Pirandola, Stefano orcid.org/0000-0001-6165-5615, Laurenza, Riccardo, Lupo, Cosmo orcid.org/0000-0002-5227-4009 et al. (1 more author) (2019) Fundamental limits to quantum channel discrimination. npj Quantum Information. 3. ISSN 2056-6387
Abstract
What is the ultimate performance for discriminating two arbitrary quantum channels acting on a finite-dimensional Hilbert space? Here we address this basic question by deriving a general and fundamental lower bound. More precisely, we investigate the symmetric discrimination of two arbitrary qudit channels by means of the most general protocols based on adaptive (feedback-assisted) quantum operations. In this general scenario, we first show how port-based teleportation can be used to simplify these adaptive protocols into a much simpler non-adaptive form, designing a new type of teleportation stretching. Then, we prove that the minimum error probability affecting the channel discrimination cannot beat a bound determined by the Choi matrices of the channels, establishing a general, yet computable formula for quantum hypothesis testing. As a consequence of this bound, we derive ultimate limits and no-go theorems for adaptive quantum illumination and single-photon quantum optical resolution. Finally, we show how the methodology can also be applied to other tasks, such as quantum metrology, quantum communication and secret key generation.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © The Author(s) 2019 |
Keywords: | quant-ph,cond-mat.other,physics.optics |
Dates: |
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Institution: | The University of York |
Academic Units: | The University of York > Faculty of Sciences (York) > Computer Science (York) |
Depositing User: | Pure (York) |
Date Deposited: | 05 Jun 2019 13:40 |
Last Modified: | 21 Jan 2025 17:40 |
Published Version: | https://doi.org/10.1038/s41534-019-0162-y |
Status: | Published |
Refereed: | Yes |
Identification Number: | 10.1038/s41534-019-0162-y |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:147001 |