Hybrid Entanglement between Optical Discrete Polarizations and Continuous Quadrature Variables

Jianming Wen,Chuanwei Zhang,Shengwang Du,Chen Qian,Irina Novikova

doi:10.3390/photonics8120552

Abstract

By coherently combining advantages while largely avoiding limitations of two mainstream platforms, optical hybrid entanglement involving both discrete and continuous variables has recently garnered widespread attention and emerged as a promising idea for building heterogenous quantum networks. In contrast to previous results, here we propose a new scheme to remotely generate hybrid entanglement between discrete polarization and continuous quadrature optical qubits heralded by two-photon Bell-state measurement. As a novel nonclassical light resource, we further use it to discuss two examples of ways—entanglement swapping and quantum teleportation—in which quantum information processing and communications could make use of this hybrid technique.

Highlights

Discrete Polarizations and Quantum entanglement is an indispensable resource for implementing optical quantum information processing (QIP) [1,2,3,4,5,6,7]
Dependent on the Bell states prepared on the nodes of Alice and Bob, we propose two different solutions to realize hybrid entanglement swapping
We notice that with some modifications, the teleportation scheme can be geared towards applications for quantum wavelength conversion between a single-photon polarization qubit and a two-mode squeezing with use of a CV quantum teleporter

Summary

Introduction

Discrete Polarizations and Quantum entanglement is an indispensable resource for implementing optical quantum information processing (QIP) [1,2,3,4,5,6,7]. We are aware of a recent work [13] that has been published with use of the DV qubits encoded in the polarizations In this DV-CV scheme, the DV polarization modes are not in a true single-photon state because they are from mixing of a weak coherent light beam and photons subtracted from a squeezed vacuum state. In contrast to the recent work with mixing weak coherent light [13], we create the hybrid entanglement using polarization entangled photon pairs and a joint two-photon Bell-state measurement (BSM) This choice helps to eliminate the effect of the vacuum and detection loss on measurement results, and remove any possible crosstalk between two encoding spaces. One can show that an entangled cat state can be established to link the two CV end nodes

Cat i

The actual teleportation takes place when

Summary