Geometry of two-qubit states with negative conditional entropy

Author(s)
Nicolai Friis, Sridhar Bulusu, Reinhold A. Bertlmann
Abstract

We review the geometric features of negative conditional entropy and the properties of the conditional amplitude operator proposed by Cerf and Adami for two qubit states in comparison with entanglement and nonlocality of the states. We identify the region of negative conditional entropy in the tetrahedron of locally maximally mixed two-qubit states. Within this set of states, negative conditional entropy implies nonlocality and entanglement, but not vice versa, and we show that the Cerf-Adami conditional amplitude operator provides an entanglement witness equivalent to the Peres-Horodecki criterion. Outside of the tetrahedron this equivalence is generally not true.

Organisation(s)
Particle Physics
External organisation(s)
Leopold-Franzens-Universität Innsbruck, Universität Wien
Journal
Journal of Physics A: Mathematical and Theoretical
Volume
50
No. of pages
26
ISSN
1751-8113
DOI
https://doi.org/10.1088/1751-8121/aa5dfd
Publication date
03-2017
Peer reviewed
Yes
Austrian Fields of Science 2012
103025 Quantum mechanics
Keywords
Portal url
https://ucris.univie.ac.at/portal/en/publications/geometry-of-twoqubit-states-with-negative-conditional-entropy(c4ccb7f7-ea51-4369-8881-5077539ac2e8).html