Quantum error-correction of continuous-variable states with realistic resources

TL;DR

This paper analyzes a quantum error-correction protocol for continuous-variable states that accounts for realistic, non-ideal resources, demonstrating potential for practical implementation with current technology.

Contribution

It extends previous protocols by incorporating non-unit efficiency sources and detectors, showing how excess noise can be mitigated through classical gain adjustments.

Findings

Excess noise can be partially compensated with classical gain tuning

Error correction remains feasible with current optical technology

The protocol's robustness improves with realistic resource constraints

Abstract

Gaussian noise induced by loss on Gaussian states may be corrected by distributing EPR entanglement through the loss channel, purifying the entanglement using a noiseless linear amplifier (NLA) and then using it for continuous-variable teleportation of the input state. Linear optical implementations of the NLA unavoidably introduce small amounts of excess noise and detection and source efficiency will be limited in current implementations. In this paper, we analyze the error-correction protocol with non-unit efficiency sources and detectors and show the excess noise may be partially compensated by adjusting the classical gain of the teleportation protocol. We present a strong case for the potential of demonstrable error-correction with current technology.