Enabling entanglement distillation via optomechanics

TL;DR

This paper demonstrates that optomechanical systems can enable entanglement distillation of Gaussian states by measuring mechanical degrees of freedom, overcoming a key limitation in quantum networking.

Contribution

It introduces a novel method using optomechanics and mechanical measurements to distill and enhance entanglement in optical Gaussian states.

Findings

Mechanical measurements can supply non-Gaussian entangled states for distillation.

Conditional entanglement increase is achievable with optimal radiation-pressure interaction.

Entanglement enhancement can be verified via standard teleportation protocols.

Abstract

Quantum networking based on optical Gaussian states, although promising in terms of scalability, is hindered by the fact that their entanglement cannot be distilled via Gaussian operations. We show that optomechanics, integrable (on-chip) availability, and particularly the scope to measure the mechanical degree of freedom, can address this problem. Here, one of the optical modes of a two-mode squeezed vacuum is injected into a single-sided Fabry-P\'{e}rot cavity and non-linearly coupled to a mechanical oscillator. Afterward, the position of the oscillator is measured using pulsed optomechanics and homodyne detection. We show that this measurement can supply non-Gaussian entangled states frequently enough to enable scalable entanglement distillation. Moreover, it can conditionally increase the initial entanglement under an optimal radiation-pressure interaction strength, which corresponds to an effective unsharp measurement of the photon number inside the cavity. We show how the resulting entanglement enhancement can be verified by using a standard teleportation procedure.