Environmental Assisted Quantum Information Correction for Continuous Variables

TL;DR

This paper proposes a method to recover quantum information in continuous variable systems affected by Gaussian noise through environmental measurements, enhancing quantum communication robustness.

Contribution

It introduces a simple environmental measurement protocol that can fully restore quantum information under certain conditions, even without perfect state reconstruction.

Findings

The protocol successfully restores quantum information in continuous variables.

Both deterministic and probabilistic strategies are effective.

Potential application in quantum key distribution to combat excess noise.

Abstract

Quantum information protocols are inevitably affected by decoherence which is associated with the leakage of quantum information into an environment. In this paper we address the possibility of recovering the quantum information from an environmental measurement. We investigate continuous variable quantum information, and we propose a simple environmental measurement that under certain circumstances fully restores the quantum information of the signal state although the state is not reconstructed with unit fidelity. We implement the protocol for which information is encoded into conjugate quadratures of coherent states of light and the noise added under the decoherence process is of Gaussian nature. The correction protocol is tested using both a deterministic as well as a probabilistic strategy. The potential use of the protocol in a continuous variable quantum key distribution scheme as a means to combat excess noise is also investigated.