English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Calculation of the quantum discord requires to find the minimum of thequantum conditional entropy $S(\rho^{AB}|\{\Pi^B_{k}\})$ over all measurementson the subsystem $B$. In this paper, we provide a simple relation for theconditional entropy as the difference of two Shannon entropies. The relation issuitable for calculation of the quantum discord in the sense that it can byused to obtain the quantum discord for some classes of two-qubit states,without the need for minimization. We also present an analytical procedure ofoptimization and obtain conditions under which the quantum conditional entropyof a general two-qubit state is stationary. The presented relation is also usedto find a tight upper bound on the quantum discord.

Progress on Quantum Discord of Two Qubit states: Optimization and Upper Bound