A1 Refereed original research article in a scientific journal
Quantum Incompatibility Witnesses
Authors: Carmeli C, Heinosaari T, Toigo A
Publisher: AMER PHYSICAL SOC
Publication year: 2019
Journal: Physical Review Letters
Journal name in source: PHYSICAL REVIEW LETTERS
Journal acronym: PHYS REV LETT
Article number: ARTN 130402
Volume: 122
Issue: 13
Number of pages: 6
ISSN: 0031-9007
eISSN: 1079-7114
DOI: https://doi.org/10.1103/PhysRevLett.122.130402
Self-archived copy’s web address: https://research.utu.fi/converis/portal/detail/Publication/40019349
Abstract
We demonstrate that quantum incompatibility can always be detected by means of a state discrimination task with partial intermediate information. This is done by showing that only incompatible measurements allow for an efficient use of premeasurement information in order to improve the probability of guessing the correct state. Thus, the gap between the guessing probabilities with pre- and postmeasurement information is a witness of the incompatibility of a given collection of measurements. We prove that all linear incompatibility witnesses can be implemented as some state discrimination protocol according to this scheme. As an application, we characterize the joint measurability region of two noisy mutually unbiased bases.
We demonstrate that quantum incompatibility can always be detected by means of a state discrimination task with partial intermediate information. This is done by showing that only incompatible measurements allow for an efficient use of premeasurement information in order to improve the probability of guessing the correct state. Thus, the gap between the guessing probabilities with pre- and postmeasurement information is a witness of the incompatibility of a given collection of measurements. We prove that all linear incompatibility witnesses can be implemented as some state discrimination protocol according to this scheme. As an application, we characterize the joint measurability region of two noisy mutually unbiased bases.
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