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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We begin with a detailed description of a low dimensional quantum channel($d_A=4, d_E=3$) demonstrating the symmetric form of superactivation ofone-shot zero-error quantum capacity. This means appearance of a noiseless(perfectly reversible) subchannel in the tensor square of a channel having nonoiseless subchannels.  Then we describe a quantum channel $\Phi$ such that $\,\bar{Q}_0(\Phi)=0$ and$\,\bar{Q}_0(\Phi\otimes\Phi)\geq\log n\,$ for any $\,n\leq+\infty$.  We also show that the superactivation of one-shot zero-error quantum capacityof a channel can be reformulated in terms of quantum measurements theory asappearance of an indistinguishable subspace for tensor product of twoobservables having no indistinguishable subspaces.

On superactivation of one-shot zero-error quantum capacity and the related property of quantum measurements