Entropic Accord: A new measure in the quantum correlation hierarchy
- URL: http://arxiv.org/abs/2205.06477v2
- Date: Tue, 8 Nov 2022 08:03:52 GMT
- Title: Entropic Accord: A new measure in the quantum correlation hierarchy
- Authors: Biveen Shajilal, Elanor Huntington, Ping Koy Lam, and Syed Assad
- Abstract summary: We show a new measure of quantum correlations which we call entropic accord that fits between entanglement and discord.
We study two-qubit states which shows the relationship between the three entropic quantities.
- Score: 0.5039813366558306
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Quantum correlation often refers to correlations exhibited by two or more
local subsystems under a suitable measurement. These correlations are beyond
the framework of classical statistics and the associated classical probability
distribution. Quantum entanglement is the most well known of such correlations
and plays an important role in quantum information theory. However, there exist
non-entangled states that still possess quantum correlations which cannot be
described by classical statistics. One such measure that captures these
nonclassical correlations is discord. Here we introduce a new measure of
quantum correlations which we call entropic accord that fits between
entanglement and discord. It is defined as the optimised minimax mutual
information of the outcome of the projective measurements between two parties.
We show a strict hierarchy exists between entanglement, entropic accord and
discord for two-qubit states. We study two-qubit states which shows the
relationship between the three entropic quantities. In addition to revealing a
class of correlations that are distinct from discord and entanglement, the
entropic accord measure can be inherently more intuitive in certain contexts.
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