Gaussian entanglement generation from coherence using beam-splitters.

Zhong-Xiao Wang,Teng Ma,Shuhao Wang,Tie-Jun Wang,Chuan Wang

doi:10.1038/srep38002

Zhong-Xiao Wang, Teng Ma + Show 3 more

Open Access

https://doi.org/10.1038/srep38002

Copy DOI

Abstract

The generation and quantification of quantum entanglement is crucial for quantum information processing. Here we study the transition of Gaussian correlation under the effect of linear optical beam-splitters. We find the single-mode Gaussian coherence acts as the resource in generating Gaussian entanglement for two squeezed states as the input states. With the help of consecutive beam-splitters, single-mode coherence and quantum entanglement can be converted to each other. Our results reveal that by using finite number of beam-splitters, it is possible to extract all the entanglement from the single-mode coherence even if the entanglement is wiped out before each beam-splitter.

Highlights

We suppose the conclusion is valid for general one-mode Gaussian states
Based on the former results, it has been confirmed by the observation that single-mode coherence and the entanglement are complementary to each other, namely, quantum entanglement increases while single-mode coherence decreases, and vice versa
The continuous variable quantum system (Gaussian state) is always difficult to be characterized by using the density matrix since the dimensionality of the density matrix is infinite

Summary

Introduction

We suppose the conclusion is valid for general one-mode Gaussian states. The continuous variable quantum system (Gaussian state) is always difficult to be characterized by using the density matrix since the dimensionality of the density matrix is infinite. The covariance matrix σ contains the elements of which is defined by[29] σ jl The covariance matrix of a two-mode Gaussian state consisting of parties A and B could be expressed as σAB = CAT

Results

Conclusion