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 Tools annual

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 monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Optical multi-mode systems provide large scale Hilbert spaces that can beaccessed and controlled using single photon sources, linear optics and photondetection. Here, we consider the bipartite entanglement generated by coherentlydistributing $M$ photons in $M$ modes to two separate locations, where linearoptics and photon detection is used to verify the non-classical correlationsbetween the two $M$-mode systems. We show that the entangled state is symmetricunder mode shift operations performed in the two systems and use this symmetryto derive correlations between photon number distributions detected after adiscrete Fourier transform (DFT) of the modes. The experimentally observablecorrelations can be explained by a simple and intuitive rule that relates thesum of the output mode indices to the eigenvalue of the input state under themode shift operation. Since the photon number operators after the DFT do notcommute with the initial photon number operators, entanglement is necessary toachieve strong correlations in both the initial mode photon numbers and thephoton numbers observed after the DFT. We can therefore derive entanglementwitnesses based on the experimentally observable correlations in both photonnumber distributions, providing a practical criterion for the evaluation oflarge scale entanglement in optical multi-mode systems. Our method thusdemonstrates how non-classical signatures in large scale optical quantumcircuits can be accessed experimentally by choosing an appropriate combinationof modes in which to detect the photon number distributions that characterizethe quantum coherences of the state.

Evaluation of bipartite entanglement between two optical multi-mode systems using mode translation symmetry