Continuous variable entanglement distillation of Non-Gaussian Mixed States

TL;DR

This paper presents a theoretical and experimental study of continuous variable entanglement distillation for non-Gaussian mixed states, demonstrating probabilistic entanglement enhancement in noisy optical channels.

Contribution

It introduces a novel method combining linear optics and homodyne detection for entanglement distillation under non-Gaussian noise conditions.

Findings

Entanglement can be probabilistically increased in non-Gaussian noisy channels.

Experimental realization using optical fibers and free-space channels.

Effective distillation demonstrated with specific non-Gaussian noise types.

Abstract

Many different quantum information communication protocols such as teleportation, dense coding and entanglement based quantum key distribution are based on the faithful transmission of entanglement between distant location in an optical network. The distribution of entanglement in such a network is however hampered by loss and noise that is inherent in all practical quantum channels. Thus, to enable faithful transmission one must resort to the protocol of entanglement distillation. In this paper we present a detailed theoretical analysis and an experimental realization of continuous variable entanglement distillation in a channel that is inflicted by different kinds of non-Gaussian noise. The continuous variable entangled states are generated by exploiting the third order non-linearity in optical fibers, and the states are sent through a free-space laboratory channel in which the losses are altered to simulate a free-space atmospheric channel with varying losses. We use linear optical components, homodyne measurements and classical communication to distill the entanglement, and we find that by using this method the entanglement can be probabilistically increased for some specific non-Gaussian noise channels.